comp.sys.hp48 FAQ : 2 of 4 - Hardware, Programs, and Programming
Andre Schoorl
Last-modified: 4/14/2000
Version: 4.62
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6.1. My HP48 seems to making a high pitched noise.
From: Dave Arnett
The guts of the HP48 keyboard are assembled from several layers of
mylar and similar material. Some of the layers have conductive ink to
create switch contacts. Some are insulators, with appropriately
located holes through which the switch contacts meet. Some are
embossed with spherically domed areas, to provide the snap-spring feel
when you press the plastic keys. The entire multi-layer sandwich is
assembled onto plastic pegs on the backside of the HP48 top case,
along with the metal chassis, and then the pegs are "heat stacked",
positively capturing and holding the matrix together.
These parallel planes can act like a capacitive speaker. Most
loudspeakers in home electronics are inductive: a sheet or cone moves
because current passes through an attached coil positioned in a
magnetic field. A capacitive speaker creates sound by moving a sheet
or diaphragm due to electric charge forces, whether attracting or
repelling. The HP48 keyboard has the necessary characteristics to be
a very inefficient (therefore quiet) capacitive speaker.
When the HP48 "scans" the keyboard, charges are placed on the parallel
sheets of mylar. They tend to move as a result of the charge, and
create a faint squeal or whine. The loudness will depend on a number
of factors, and can vary significantly from HP48 to HP48. Some folks
report that, on their HP48, the sound is stronger on the back than on
the front; others report the opposite.
6.2. Can I upgrade my S or G to more than 32K ram?
It is possible to do this by opening up the case and adding some
memory chips. There are several containing instructions and
schematics available at:
<http://www.hpcalc.org/docs/opening/>
There is a web page on how to open your HP48 from the back at
<http://www.contrib.andrew.cmu.edu/~drury/how2open.htm>
This is an illustrated guide on how to open your HP48 from the back.
It has full instructions, as well as 15 pictures of the calculator in
various stages of disassembly.
An alternate way to open your HP48 and upgrade it to 256K is described
at the following site, along with lots of pictures:
<http://studwww.eurecom.fr/~grundsch/>
Another good site is:
<http://www.geocities.com/CapeCanaveral/7584/index.html>
WARNING: It is possible to ruin your HP in the process of performing
any one of these upgrades. Do not even attempt it unless you are
adept at working with small electronics. The FAQ maintainer and the
authors of the instructions take no responsibility for anything you do
to your HP!
6.3. Can I add a lithium battery backup?
From: Lee Studley <RStud...@aol.com>
I recently did a modification to my 48G by replacing the 32K ram with
a surface mount 128x8 RAM. Afterwards, I sandwiched 2nd and 3rd RAM
chips by stacking them up and soldering. The 2nd CS was jumpered over
to the expansion pin 21a. The decode for the 3rd part was easy to
figure out. I've also added a lithium battery to insure memory
retention. This thing now has 128K user memory, 128K in port 1, and
128K in port 2. Additional port 2 chips can easily be added.
The 3 volt lithium battery used was the generic coin type. I just made
room for the holder and battery by removing the aluminum shield up to
the plastic post near the piezo element. The positive terminal of the
battery goes through a 470 ohm resistor into the anode of a schotky
diode (only 0.2 volt forward drop). The cathode end of the diode
feeds the positive side of the big 1000 uF capacitor near the added
74HC00. This is the memory retention cap when the batteries are
removed.
This way, the lithium battery only gets used if the main batteries are
removed or very low. Seems to work well so far. The ground
connection broken by cutting the aluminum shield kills the reset and
piezo contact points. To fix this, I stretched the original piezo
contact spring and cut it in half. Then I soldered the cut piece to
the ground "twisted" tab near the original spring. (readers should
verify this ground with a meter.) This restored the lost functions.
6.4. How can I get/build a cable for my HP48?
Some places that sell the HP48 also sell the cable required for
interfacing with a PC. Unfortunately, most don't.
For information on how to build your own cable, see Appendix D-1.
If you want to buy one, there are a few options. Places like ElekTek
sell them for around $20-$25.
There are a few netters that make cables for sale also. Contact:
o Chris Edmunds <ch...@muffet.com> Web page:
<http://muffet.com/hp/cables/ad.html>
o Joel Kolstad <kols...@peak.org>
o Greg Lousteau <gr...@gregjeff.com>
<http://www.gregjeff.com/greg/cable.html>
If you live in a larger city, you can look in the Yellow Pages for a
listing of HP authorized dealers who either have the cables in stock
or can order them in about the same time a mail order place can, but
for a lower price..
6.5. HP seems to offer two link kits with different prices.
HP offers two link kits, one which sells for about US$20, and the
other which sells for about US$50. The only difference between the
two is the higher priced kit comes with software and a manual. The
cable, however, is the same in both kits.
As mentionned in the next question, free alternatives to this software
are readily available. HP's software also includes some assorted
miscellaneous programs and games, all of which are also available from
HP via FTP or WWW.
6.6. Is there any communications software available?
In Windows 3.x you can use Terminal (in Accessories). In Windows 95
and OS/2 Warp, HyperTerminal can be used, or you can use any other
"terminal emulator" package with some level of embedded Kermit file
transfer capability.
However, the most complete functionality is available with full
Kermit, which can be downloaded from <ftp://kermit.columbia.edu/> or
HP. Columbia University is the original site for Kermit and has
versions for nearly all operating systems, including all forms of
Unix, Amiga, and Macintosh.
Of course if you have a G/GX machine you can use X-Modem instead of
Kermit (X-Modem is generally faster). [Hyper]Terminal works fine for
X-Modem as well. Alternative file transfer software is available from
the FTP sites mentionned in the Appendix, or can be purchased (e.g.
Donnelly's HP48 File Manager).
Also of interest are several freeware/shareware programs, including
the HP48 Explorer for use with Windows 95. This can be obtained at
<http://members.tripod.com/~nberry/hp48g/index.html>.
6.7. Why doesn't the I/R port work farther than a few inches?
It turns out that it is the receiver that is "crippled". The transmit
range is somewhere around several feet, and some people have actually
written programs to make the HP48 emulate some remote controls (see
Appendix E-1 for suggested programs).
There are currently two stories going around as to why. I will
present both of them in the interest showing all sides of the story.
You are free to decide which you believe:
1. The head of the HP48 design team, Dr. William Wickes himself,
alluded during the Chicago Handheld Conference that the IR was
intentionally crippled due to the concerns of certain individuals
in academia that students could literally 'beam' information from
one 48 to another during examinations. (from Rick Grevelle)
2. The reason the IR reception distance is so short is battery
capacity. The Infrared Transmitter is semaphore: It is only turned
on when it needs to be on, and the transmission protocol is defined
to minimize the ON time. The receiver, by contrast, must be on
continually when a transmission is in process, or when a
transmission is expected. If you set your HP48 to Server mode, that
receiver is drawing power. If you tweak the control bits to
activate the receiver for any other reason, it is drawing power.
The instantaneous peak power drawn by the transmitter is much
higher than that of the receiver. But in the long run, the
receiver will draw more energy from the batteries. Increasing the
receiver sensitivity costs even more power.
6.8. Can my HP48 talk to my HP100LX via Infrared?
Yes, it can, although slowly. Set the HP100LX at 2400 bps, and put it
in server mode (under the Kermit Commands menu). Then you can send
stuff from your HP48 to your HP100LX.
6.9. Can I use my HP48 to communicate with IrDA devices?
From: David Johnson
I have had great success communicating via IR with my HP48 GX rev. R
and a NEC Versa 6050MH notebook PC. However, I have found that speed
is limited to 2400 bps. I have successfully used IR communication
under Win95 with DOS Kermit 3.14, HyperTerminal, HP48 Explorer, Yellow
Computing Transfile Win 48, and Kermit v0.85 (Win32).
I have had no success with Grab48 screen capture by HP or with HP PDL
(only because I can't use a port higher than COM2). In my case DOS
Kermit requires a command like:
set com3 \x03E8 \9 ; Syntax for nonstandard address or irq
Which is the port and IRQ specified in my BIOS setup. It doesn't seem
to matter what IR speed I choose in the BIOS setup. However, in all
cases (even native Win95 applications) I must disable the IR drivers
in Win95 and talk straight to the port/IRQ specified in the BIOS. I
can easily turn IR support on and off within a Win95 session with no
ill effects via the control panel.
Note that the HP48 is not actually IrDA compatible, but communicates
with IR devices in non-IrDA mode.
6.10. Can I print to a LaserJet printer with an HP48?
From: Derrik Pates
Yes you can, but you need the HP PCL library from
<http://www.hpcalc.org/utils/misc/pcl.zip>. It allows you to
communicate with any printer that supports PCL (all HP DeskJets and
LaserJets, as well as some other laser printers and inkjet printers).
You can hot-switch your resolution and turn PCL on/off with software
commands.
Although newer HP printers such as the 5P and 5MP have an IR port, you
cannot use it to print directly from your HP48.
6.11. I downloaded a program but all I get is "HPHP48-..."!
Some versions of Kermit distinguish between ASCII and binary files,
and so you have to worry about the transfer modes at both ends of the
connection (the HP48 SX end and the computer end). For example, when
receiving ASCII files, Unix Kermit must translate CR/LF pairs into LF.
If the HP48 SX is transmitting a binary file, but the Unix Kermit is
expecting ASCII, any CR/LF pairs in the binary file will get
translated to LF, corrupting the binary file. Unfortunately, you
cannot "uncorrupt" the corrupted binary file by simply reversing the
transfer and expecting Kermit to translate LF to CR/LF. This is
because the binary file may contain occurrences of LF that were not
originally part of a CR/LF sequence.
When a binary file gets corrupted, it will display on the stack as a
string, starting with the characters "HPHP48-", and continuing on with
a bunch of garbage. Thanks to two programs, these strings can be
reconverted to binary files right on the HP48. These programs are:
FIXIT, by Joe Horn and Mika Heiskanen, or OBJFIX, written by our
friends at HP. These are included in Appendix A-2.
The major difference between FIXIT and OBJFIX is the way they operate.
I have never personally had any problems with either. FIXIT takes the
bad "HPHP48-" string from level 1 of the stack, and replaces it with
the correct binary object. OBJFIX takes the name of the variable in
which the "HPHP48-" string is stored from level 1 of the stack, and
puts the correct binary object directly in the variable where the bad
string was stored. It's up to you which you prefer. I would suggest
reading the documentation of both before using either of them.
There is also a quick fix available from Dan Kirkland:
Here is a simple SYSEVAL program that will return a pointer to the
object in those data transfer strings that start with "HPHP48-"
Checksum: # 8FEh
<< "12" SWAP + # 402Bh SYSEVAL # 62B9Ch SYSEVAL >>
That's all! (Simple huh!) Name? Whatever you want!! Works on all
48s (S/SX, G/GX)
6.12. What is the structure of HP48 ASCII headers?
From: Jorge Costa
ASCII file headers such as %HPHP: T(3)A(D)F(.); are created by the
HP48 when an ASCII file is sent to the PC and read when a HP48 ASCII
file is received from the PC. They serve to preserve various settings
on your HP that affect ASCII transfers. They do not affect binary
mode transfers.
Three parameters are saved: (T)ranslation Mechanism, (A)ngle Mode, and
(F)raction Mark.
Translation Mechanism:
The possible ASCII translation schemes are as follows:
T HP48 -> PC PC -> HP48
---------------------------------------------------------
0 No translation No translation
1 char 10 -> chars 10,13 chars 10,13 -> char 10
2 Action 1 & translate Action 1 & translate
chars 128 - 159 \000 - \159 to HP48 chars
3 Action 1 & translate Action 1 and translate
chars 128 - 255 \000 - \255 to HP48 chars
To choose your favorite set, just type the number followed by the
command TRANSIO on the HP48 command line. Depending on which
translation scheme you are using, the HP48 converts a different set
of characters to PC ASCII format. I would advise using option 3,
since this forces the calculator to translate all symbols to pure
ASCII (look for the table in page 27 - 16 of the HP48G series
user's guide). If you choose to use option 0 or 1, all characters
from code 128 to 255 would be interpreted following the current
code page of the PC setup - it will be unreadable!
Also, if you are receiving ASCII files in your machine and you get
a bunch of black squares, you can be fairly certain you are using
translation mode 0, which makes the HP receive and store all
newline characters (instead of eliminating them).
Angle Mode:
o A(D) stands for degrees.
o A(R) stands for radians.
o A(G) stands for gradians.
Fraction Mark:
The HP48 can handle two types of fractions marks - the decimal
dot or comma. This option is available from the MODES input
form (48G/GX) or menu 64.01.
With regards to the ASCII header we have:
o F(.) means the format is dot.
o F(,) means the format is comma.
If you try manually editing an ASCII file on the PC without a
header, then try to send it to the HP48 using Kermit, you can
obtain the following results:
Number format Text sent Result (object stored)
. 3.4 3.4
. 3,4 3 4
, 3.4 3 4
, 3,4 3,4
As you would expect, sending files with ASCII headers to the HP48
with mismatching fraction mark settings, leads to an "Invalid
Syntax" error during transfer.
Now take a look at rows 2 and 3 of the table above - the object
received by the HP48 is stored as a program object without the <<
and >> composed by two real numbers - well, that normally can't be
done in User RPL!
In fact the resulting object is a very simple System RPL program
object (the internal language of the HP48). The conclusion is that
when a file is sent without an ASCII header, the HP48 translates
numbers with mismatching formats into System RPL secondaries
(programs) of the form:
:: %IntegerPart %FractionalPart ;
6.13. Why do Kermit transfers seem to get slower?
From: Dan Kirkland
The reason the HP48 Kermit routines are so slow is because they are
written in System RPL. Everytime the HP48 receives a packet (received
as a string), it copies the previously received packets (string #1)
and the new packet (string #2) to a new string (which becomes string
#1 when the next packet is received). This is why the HP48 Kermit
gets slower and slower on big transfers (string #1 just keeps getting
bigger).
As to sliding windows... Sliding windows really don't help much with
a clean, lag-free connection. And as most people connect their HP48
directly to the computer they are transfering to/from with a very
short line, it is almost always very clean and lag-free. So, sliding
windows have very little to offer HP48 transfers.
Yes, properly written Kermit routines should be at least as good as
ZModem, even without sliding windows. And with a dirty, lagged
connection, Kermit with sliding windows will blow ZModem away. But
then, this just doesn't happen very often with HP48 connections.
Some claim that the HP48 can't do ZModem without tons of trickery
because it doesn't have a large enough input buffer. While this is
true, it shouldn't be too hard to do. And the same is true for Kermit
if it is going to get ZModem type speed! Small packets are more
reliable, but much bigger packets are needed for speed.
6.14. Why does XRECV not work sometimes? (GX)
Pre-Rev R. G Series 48's had a bug that would sometimes cause XRECV to
fail if there was not twice the amount of room free for the incoming
file. FXRECV, a fix for this bug, is available on the Horn 9 disk in
the directory \HP as FXRECV. There is more info about this bug there
as well. Note that FXRECV is not required for Rom R, and in fact
will not run properly on Rom R.
6.15. Additional Tips on Transfers
To use the least memory when doing transfers, it is a good idea to use
the built-in "Transfer..." application only to set parameters (Wire,
Baud, etc...) but not to actually start a transfer with it; instead,
press ENTER, then do either left-shift RECV (Kermit) or 0 FXRECV
(Modified X-Modem). Avoiding the fancy "dialog box" application
leaves more memory free at the time of actual transfer.
For best quick-start of a transfer, start the Kermit receive side
before the transmit side. For X-Modem the opposite is true: start the
transmit side before the receive side (with only a short interval
between each side's start). Experiment a bit to find out what works
best for you.
Here is a small program for Kermit that lets you receive directly to a
port:
\<< -36 SF 1 \-> a \<< 'a' RECN a \>> SWAP STO \>>
For the argument use either just a number (if receiving a library) or
a port-tagged name such as :0: name (for other objects, and in fact
for libraries as well, but only the port number is used).
This program may be simpler to follow than the User's Guide directions
for installing a library, since it encapsulates the several steps of
storing in memory, recalling to stack, purging the variable, and
finally storing to a port. Even if you forget to supply the portname
argument, the received object will still appear on the stack (provided
flag -55 is clear), and you can finish storing it afterwards.
6.16. What do the funny symbols in this document mean?
The symbols in this document such as \-> and \GS+ are the ASCII
representation of the special HP48 graphical characters. See the
section "Character Translations" in the manual for a complete table of
symbols <--> ASCII representations.
SX:
Chapter 33 (Volume II if 2 volumes)
GX:
Page 27-16 HP48 G Series User's Guide
6.17. What are the pinouts for the HP48 serial connector?
Looking at the pins of the HP48 (the following diagram is showing the
pins on the HP48, as you look at the calculator):
_________
| o o o o |
\_______/
^ ^ ^ ^
| | | \------ 4 Signal GND
| | \-------- 3 RX (input to the HP48)
| \---------- 2 TX (output from the HP48)
\------------ 1 SHIELD
Stated another way:
HP48 IBM 9 PIN IBM 25 PIN
(From the outside
edge -> inward)
SHIELD------------------- SHIELD---------------- SHIELD
TX (Output)<-------------2 RX (Input)------------3 RX (Input)
RX (Input)-------------->3 TX (Output)---------->2 TX (Output)
SGND---------------------5 GND-------------------7 GND
This information is also on page 27-7 of the G/GX manual.
6.18. Is there any information on interfacing to the HP48?
HP has made available an UNSUPPORTED document called the "HP48 I/O
Technical Interfacing Guide", which contains information on the wired
and serial I/O hardware. Another HP document available is the "HP48
I/O Software Interfacing Guide". Also, there are a number of guides
contributed by users on making your own serial/IR hardware.
Look at <http://www.hpcalc.org/docs/programming/> as well as the ftp
sites listed in the Appendix. If you find a good document, let me
know so I can put it here!
6.19. How can I transfer programs/data from my HP-28S to my HP48?
You use a program called "INPRT", which is available on GD #9. Any
previous version will crash the GX. The new version's checksum is
#EDF3h, and the old, SX-only version's checksum is #2280h.
For each program that you want to transfer, you use the HP 28S to
print it to the I/R output; INPRT, running on the HP48, reads the I/R
output of the HP 28S and converts it into a program string.
6.20. Can I use rechargeable batteries with the HP48?
The Rayovac "Renewal" batteries have proven themselves to be reliable
in the HP48, but there are some problems with Nickel Cadmium (Ni-Cad)
batteries. You'll have to decide if using rechargeable batteries is
worth putting up with the problems associated with them:
o You'll have to change batteries more often with rechargeable
batteries. Alkaline batteries can deliver power for a longer
period of time, compared to rechargeable batteries.
o Once the low-battery indicator comes on, you'll have to change the
rechargeable batteries pretty quickly. With rechargeable
batteries, you have only a few minutes before the calculator dies
(it's been said that you have up to 15 minutes or so). With
alkaline batteries, you have an amount of time that is supposedly
measured in hours.
o Ni-Cad batteries lose their charge with time, even if you are not
using them. Even if a Ni-Cad battery is just sitting unused on a
shelf, it slowly loses its charge. Alkaline batteries keep their
charge for a very long time.
6.21. How can I tell, from within a program, if the battery is low?
The following 48 program reports the status of the ALERT annunciator.
The ALERT annunciator is activated by alarms or low battery.
This program is provided free of charge "as is" and has no warranty.
No one is liable for any consequential damages. Preston
%%HP:T(3)A(D)F(.);
\<<
RCLF
8 STWS #FFh #0h +
#10Bh
#6595Ah SYSEVAL
#8h AND #0h >
SWAP STOF
\>>
6.22. I lost the information on my RAM Card when I changed the bat-
tery!
You forgot to turn ON the calculator before changing the battery. The
HP only supplies power to the RAM card while the HP is turned on.
While the calculator is turned off, no power is supplied by the
calculator, and all power comes from the RAM card battery. If you
then take out the battery from the RAM card while the calculator is
turned OFF, the RAM card has no source of power, and you will lose all
of the contents in the RAM card.
6.23. Why do I get an "Invalid card data" error when I merge a RAM
card?
This message is usually seen when you plug a brand-new RAM card into
an HP48. In this case, this message is normal and is harmless. It
just means that there was no (valid) data on the card.
GX:
This message can appear when a RAM card contains ports you have
never used. Press purple/left shift-LIBRARY. Hit NXT, then the
PINIT softkey. This will initialize all available RAM ports.
It does not affect data already stored on the card.
If you see this message under any other conditions, it could be
one of the following:
1. You took the battery out of the RAM card while the card was
out of the calculator, therefore erasing the memory.
2. You took the battery out of the RAM card while the card was
in the calculator BUT the calculator was turned off. Note
that the calculator supplies power to the RAM card ONLY when
the calculator is turned ON. Again the memory on the card is
gone.
3. The RAM card battery is dead.
4. There is a problem with either the calculator, the RAM card,
or both.
If the battery is operational, then try to store something on
the card. If you still get the error message, then backup all
your info to a computer or another 48, and do a hardware reset.
6.24. I've heard about other manufacturer's RAM cards. Will they
work?
While some cards may work, there is a chance that you may severely
damage your HP48. You should only use cards specifically designed for
the HP48. Naturally, HP sells such cards, and some third parties also
make cards that will work in an HP48. Some cards work with both the
S/SX and the G/GX. Some, however only work on the S/SX, or only on
the G/GX. Make sure that the card is designed to work for your
version before using it.
SX:
The S/SX can only naturally support up to 128K per port. HP
sells 32K and 128K RAM cards. However, TDS, using software
"bank switches" produces 256K and 512K RAM cards. These bank
switching cards do not work in the G/GX series. CMT also makes
128K cards, which work in all HP48 calculators.
GX:
While you cannot use the TDS 256K and 512K cards, Sparcom has
come out with 256K and 512K cards for the G/GX only. HP also
sells 1MB RAM cards that work for G/GX only. The G/GX is able
to accept a 4MB RAM card, but none are on the market at this
time.
6.25. How does RAM card locking work?
From: Dave Arnett
The HP48SX had three layers of write protection:
o The Seiko-Epson memory cards contain write protection. Seiko-Epson
is the OEM manufacturer for HP brand cards. They developed the
format, connector and pin definitions for the memory card
interface. We have a slightly modified version of their standard
card where the low battery alarm limits are changed slightly.
On an HP-branded RAM card, if you move the write-protect switch to
the Protect position, two things happen. First, the card itself
ignores write cycles. This is the first layer of defense for data
integrity. The card also changes the voltage level of one of its
output pins to tell the HP that it is write-protected.
o The HP CPU chip detects the write protect indicator line of the
card. If it is reporting as unwriteable, the hardware locks out
write functionality from the CPU chip. This is the second layer of
defense. If this Card Detect line reports as writeable, then write
transactions are permitted in hardware. If the Card Detect line
floats, the hardware reports that no card is installed.
o The HP system firmware checks the status of the write protection
bits before writing to a memory card. If the status bits indicate
that the card is unwriteable (ROM or protected RAM), then the
system code refuses to write to the card.
In developing the HP48GX, we changed card handling in some significant
respects. I have recently posted information to the newsgroup on how
the upper half of ROM and the card slot 2 are controlled through one
pin of the Yorke CPU IC in a multiplexed fashion. There are some
details about the Yorke chip related to how various Saturn Bus deviced
configure and unconfigure which required me to make the following
hardware assignment changes:
Hardware Resource HP48SX HP48GX
CE1- Card Controller 1 Card 1 Bank Select Controller
CE2- Card Controller 2 Card 2 Card 1
CE3- Card Controller 3 Unused Card 2
CDT1- Card Detect 1 Card 1 Card 2
CDT2- Card Detect 2 Card 2 Card 1
Clearly, we had to assign Card Controllers and Card Detects in pairs,
as much as possible. Otherwise the hardware lockout would make a mess
of things.
A write protected RAM card in GX slot 1 has hardware lockout
protection, since CDT2 can lock write actions to CE2.
A write protected RAM card in GX slot 2 does not have the same HP
hardware protection. CDT1 is hardware coupled to CE1, which drives
the Bank Select Controller. Some may have wondered in my recent posts
why the protocol for setting up bank settings uses READ operations
rather than WRITE operations. Now you know: A WRITE operation to the
Bank Select Controller would be ineffective if a ROM or Write-
Protected RAM card is in Slot 2!
The closest approximation to hardware write protection lies in the BEN
(Bank Enable) line, which is bit 6 of the Bank setting. Unless BE is
set high, all attempts to access slot 2 are forbidden. BEN is pin 10
of the 74HC174 chip. This line goes to pin 5 of the NAND chip to
prevent Card Pin 21 from going active.
The protocol in the HP48GX RPL Opertaing System implementation is to
always leave BEN low, unless slot 2 activity is needed. BEN should be
set low again after card access is complete.
So an HP48GX has three levels of card write protection as well:
o The card should prohibit Write activity if the protection switch is
set.
o Slot 1 has the same hardware lockout as in the SX. Slot 2 has a
multi-step process necessary to enable access.
o The RPL system code checks the write-protect status before writing
to a card. It understands that CDT1 and CE3 map to card 2.
6.26. What are the advantages and disadvantages of covered ports?
(GX)
Covered ports are created when a card is placed in slot 2 of the GX,
that is all ports >= 2. The advantage of this is very large RAM cards
are possible: 256K, 512K, etc... up to 4 MB. Cards larger than 128K
are split into multiple ports of 128K each controlled by a bank
switching mechanism.
The disadvantages are that the memory cannot be merged with user
memory (even if only a 128K card is used). Furthermore, some programs
may be sensitive to the bank switching in covered ports, and may run
slightly slower, improperly, or simply refuse to run at all. In
particular, many of the freeware programs written in machine language
are affected. Some contain special code to allow them to execute from
both covered and standard ports.
6.27. Why does the HP48 display flicker slightly?
Display flicker is usually caused by fluorescent lights. The rapid
pulsing of the fluorescent lights (60 Hz in the the U.S. and Canada),
which is normally unnoticeable, interacts with the rapid
pulsing/scanning of the HP48 LCD display (64 Hz refresh rate), which
is also normally unnoticeable. The 60 Hz fluorescent lights alias
with the display refresh (64 Hz) to produce a 4 Hz "flicker". It's
normal and harmless.
Outside the U.S. and Canada, power is supplied at a 50 Hz rate, not 60
Hz. This means that the display "flickers" at a 14 Hz rate, which is
still noticeable.
6.28. I broke the LCD screen - is there an easy way to get another?
Unfortunately, as far as I am aware, you cannot get a replacement, the
cheapest alternative is to send the calc in for "standard service" at
HP, which is slightly cheaper than a new calculator. Opening an HP48
is quite difficult anyway.
6.29. How can I protect my LCD?
There are many ways to protect the HP48's LCD. The solutions include:
o Inserting a piece of cardboard into the case.
o Cutting plexi-glass and putting it into the case (slightly better
than cardboard). A piece of plastic cut out of a CD jewel case
works too.
o Even better than plexiglass (because it's really unbreakable and
will resist any twisting) is an electronic circuit board as used
for computer mainboards etc... which should be available in any
electronics shop. Another advantage to this method is the possible
electrical shielding you get if there is a thin film of copper on
one or both sides. I would recommend a board with the copper on
one side only - on the side pointing to the outer side of the HP's
soft case. After sawing it to the dimensions 79.5 mm x 179 mm x
1.25 mm and rounding the four corners (radius 4 mm), it will fit
perfectly in the inner sleeve of the HP48's soft case and can also
be used to hold a self-adhesive label with the owner's name. The
small messages booklet will still fit, but it is better to store it
on the outer side of the board so that the circuit board and the
calculator will still fit together as tightly as possible
(otherwise the booklet may break the LCD).
o Buying a hard case. A variety of types are available, including a
hard leather case or a totally waterproof case.
o Keeping it in a video cassette or pencil case during transport.
o Using the cover from an old TI-8x calculator and fitting it into
the grooves on the side of the HP48. Some people have had some
success with this, but I find it barely fits.
6.30. Is there a rigid (protective) case for the HP48?
An inexpensive solution to this is to go to Sears and get a Black
Plastic Tool Box #9 65283 in the hardware deptartment. It sells for
only US $4.95. The case is big enough for the calculator in its case,
plus extra batteries.
The case is a good fit for the calculator. If you want to go a step
further, you can get some foam, glue it into the top and bottom halves
of the case, and cut out a calculator shaped hole in the bottom. The
result is lightweight, strong, secure and still leaves a little room
for you to store extra batteries, a cable, and/or cards for your
ports. Another solution is to use a cheque book as a case. Some
cheque books just happen to fit the HP48, and provide a fair amount of
protection.
The final alternative is to purchase a case. Eric Finley
<etfi...@ucdavis.edu> sells protective hard cases for the HP48. They
are stainless steel, very strong, and look nice. The cost is US $30.
For more information, either e-mail Eric or check his web page at
<http://www.ece.ucdavis.edu/~etfinley/>.
6.31. Can I use my Amateur Radio with my HP48?
Yes, however you need to have a few things, the first being an amateur
radio license. The next thing you need is a terminal node controller.
If you are able to, get a terminal node controller that supports XON
and XOFF software flow control. This is good to have because the HP48
only has a 256 character buffer. When the buffer is full, the HP48
sends the "buffer full" signal and a terminal node controller with
software flow control can quit sending data until the HP48 can keep
new data in the buffer. If you don't have a terminal node controller
with software flow control, you can still use it, but you may lose
some data.
The next thing you will want is some software to use with the terminal
node controller. You could make your own software using user-rpl
commands such as BUFLEN, SRECV, and XMIT. However, there is a
plethora of software available. All you need is software then can
send and receive data from the serial port. There are several
programs at <http://www.hpcalc.org/utils/comms/terminal/> that you
might like to try.
There is also a site that has a lot of hp48 programs relating to ham
radio. Connect to <ftp://oak.oakland.edu/pub/hamradio/hp48/> Please
inform the FAQ maintainer if you find additional software, so it can
be added to this list.
7. Questions about programs
7.1. Where can I get programs and information for the HP48?
See Appendix E-1 for more info.
7.2. What are the Goodies Disks and where do I get them?
See Appendix E-5 for more info.
7.3. How do I get access to the HP Calculator BBS?
You can also access the BBS online at
<ftp://ftp.hp.com/pub/calculators/>
You can also access the HP Calculator BBS via a modem (note that this
is a long distance call for most people):
(208)-344-1691 2400 bps, 8N1
(541)-715-3277 9600 bps, 8N1
See Appendix E-4 for more BBS sites.
7.4. What are files that end with ".zip", ".Z", ".gz", or ".bz2"?
zip
Files that end with ".zip" are pkzip archives, which originated
in the MSDOS world. One program that can extract the files in
".zip" archives is the InfoZip "unzip" program.
Binaries and source can be found at
<http://www.cdrom.com/pub/infozip/>
gzip
Files that end with ".gz" have been compressed using the "gzip"
compression command. To uncompress these files, you must use
either the "gunzip" or "gzip -d" command. The "gunzip" program
can also uncompress ".Z" files. Binaries should be on all Unix
systems, but if not you can try <ftp://ftp.gnu.org/pub/gnu/>
More information should be there on binaries for other
platforms.
compress
Files that end with ".Z" have been compressed using the Unix
"compress" command. To uncompress these files, you can use the
"uncompress" command on Unix. The "gunzip" program can also
decompress these files.
bzip2
Another compression program gaining popularity is bzip2. bzip2
is a freely available, patent free, high-quality data
compressor. It typically compresses files to within 10% to 15%
of the best available techniques, whilst being around twice as
fast at compression and six times faster at decompression.
Source and binaries for common platforms are available at
<http://www.muraroa.demon.co.uk/>
7.5. What is a "ship" file?
In the past, programs for the HP48 posted on comp.sources.hp48 were
posted in the "ship" format. This format made it easier for the
moderator to distribute programs, but made it more difficult for users
to extract and use these programs. Some people still use ship.
To extract programs distributed in the "ship" format, you need the
following:
1. A copy of the "ship" program, compiled for your platform.
o Sources for ship can be found at
<ftp://ftp.cis.com/pub/hp48g/dos/unship.zip> which also includes
the DOS executable.
o Binaries for other platforms can be also be found at
<ftp://wuarchive.wustl.edu/systems/hp/hp48/Posting/>
2. A copy of the latest InfoZip "unzip" program or an unarchiver that
understands the pkunzip v2.04g format. Note that you cannot use
older unzip programs, as old unzip programs do not understand the
new compression formats. See the previous section for information
on where to get source and binaries.
Once you have a copy of the "ship" and "unzip" programs, you use
"ship" to convert the ship-encoded file into a .zip file, and you use
the "unzip" program to extract the HP48 files from the ".zip" file.
7.6. What is the ASC format and how can I use it?
The functions ASC\-> and \->ASC were written by William Wickes to
facilitate transferring HP48 binary objects in an ASCII format (useful
when transferring objects via electronic mail or bulletin boards).
Some HP48 objects, like libraries, cannot normally be converted into
ASCII, unlike program objects, and these functions make it possible to
do so.
The \->ASC function converts the object in level 1 into an ASCII
string, which can then be uploaded to a computer for mailing.
The ASC\-> function converts the string object in level 1 back into an
object. A checksum is used to ensure that the decoding is correct.
A copy of these programs are given in Appendix A-1, near the end of
this file. Note however, that these functions aren't used much
anymore. The standard in the newsgroup seems to first zip the
programs together and post them uuencoded. But, you may still need
these utilities for extracting older files you download.
7.7. What is the HYDE library, and how do I get rid of it?
The HYDE library is a library that changes the messages on your HP48.
It works on all versions of the HP48 and is available on Goodies Disk
2. The program (HYDE.TXT) is in the DNICKEL directory needs to be
converted with ASC\->. The instructions (HYDE.DOC) for the program
are in the HORN2 directory. The library is 3679.5 bytes, small enough
to keep on your HP48 so you can install it on a friend's when they're
not looking.
Follow the previous instructions for installing the library, then go
to the library menu and run HYDE.
However, getting rid of the HYDE library is a little trickier. First
you must type JEKY on the command line. This will disable the HYDE
library and restore the standard set of messages. Then you can follow
the normal instructions for deleting a library.
7.8. What is the Minehunt game, and how do I use it?
The Minehunt game is a game built in to the G/GX. It was also
included on the HP Equation-Library Card (for the HP48 SX).
GX:
It is located in the UTILS menu of the left-shift(purple) EQ LIB
menu. (Left-Shift {EQ LIB], {UTILS}, {MINEHUNT}). See page
25-14 of the manual for a game explanation and picture.
SX:
It is located in the UTILS library.
You can save a game by pressing the STO button. This creates a
variable with the name MHpar. If you are in the directory containing
that variable, you will resume your old game when you run MINEHUNT.
To select the number of mines for your next game just store a number
in a variable, Nmines (it's case sensitive), and you'll get that many
mines. If you store a negative number, you'll get the absolute value
of that many mines, AND all mines will be visible.
You can also move diagonally if you use the numbers as arrows: 1 is
down+left, 2 is down, 3 is down+right, 4 is left, 6 is right, 7 is
up+left, 8 is up, and 9 is up+right.
8. Questions about programming and advanced user functions
8.1. I've heard the names RPL, Saturn, STAR, GL etc... What are
they?
ASAP
This is a simple Saturn assembler, written in the Perl language.
Chip8, Chip48, Schip, Schip8
This is a machine-code program that was inspired by the chip8
video game interpreter for the RCA CDP1802 microprocessor
several years back. Chip8 allows you to write a simple
graphics-based video game for the HP48 SX. Among the games
written are "clones" of Breakout, PacMan, and Pong, to name a
few.
Chip48, Schip and Schip8 are two different names for an enhanced
version of chip8 specifically designed for the HP48 SX. People
have written programs to assemble Schip assembly language into a
form directly usable by Schip on an HP48. Schip interpreters
are available for both G and S series.
GL GL (Game Language) is a language for the programmer who wants
almost the speed of assembly, but who doesn't want to spend a
lot of time and effort to learn all the tricks of assembly
programming on the HP48. GL has an assembly-like syntax, and
there is an assembler for PC and one for the HP48 itself. Since
GL is an interpreter, the GL library (3 KB in size) must be
installed on the HP48 to run GL programs. The instruction set is
powerful, with sprites and pixel based graphics, scrolling,
sound, keyboard control, and more. There are 256 1-byte
registers which can be used in pairs as 2-byte words. A GL
program can be up to 64 KB in size. GL was inspired by SCHIP,
but it is much better in all aspects. It is suitable for many
applications, not only games, that require high speed. Of
course it works on both the HP48 S/SX and the G/GX. GL is
written by Erik Bryntse.
Java
Java is a library that displays an improved 5 level stack. It
combines the best of SOL, HPSauce, EQStk, and others. Plus
there are several new features and improvements! The intent of
Java is to provide a more useful and faster stack environment
for HP48 calculators.
The HP48 Java library has no connection at all to the Sun
Microsystems product of the same name. Since the Java library
is not a commercial product, we do not expect this to a problem.
Jazz
This is best System RPL and Machine Language development library
that runs right on your HP48! Written by Mika Heiskanen. The
Jazz library provides commands for assembling, disassembling and
debugging both System RPL and machine language.
ML Machine Language. This is usually used in reference to HP48
assembly language programming.
MLDL
Machine Language Development Library. This is a library that
allows you to debug machine language programs with only an HP
48.
PDL
"Program Development Link". This is an DOS program, sold by
Hewlett-Packard, that allows you to write and develop HP48
applications from your IBM PC clone. Programs are written on
your PC, transferred to the HP48, and tested from your PC (and
not the HP48).
RPL
RPL is the name of the language used to program the HP48 and
HP-28 series calculators. RPL stands for "Reverse Polish Lisp".
It's interesting to note that an HP Journal article incorrectly
described RPL as "ROM-based Procedural Language".
From Bill Wickes:
RPL stands for Reverse Polish Lisp. In the early days of RPL
development, we got tired of calling the unnamed system "the new
system," and one of the development team came up with "RPL,"
both as a play on "RPN" which has been the loved/hated hallmark
of HP calcs forever, and as an accurate indication of the
derivation of the language from Forth and Lisp.
RPL was never particularly intended to be a public term; at the
time of the HP Journal article (August 1987) on the HP 28C there
was an attempt to create a less whimsical name--hence "ROM-based
procedural language," which preserved the initials but had a
more dignified sound. The development team never calls it
anything but (the initials) RPL. You can choose either of the
two full-word versions that you prefer. Or how about 'Rich
People's Language?'
SASS
SASS is a simple Saturn assembler, written in C/yacc (BSD Unix &
Bison). It uses Alonzo Gariepy's mnemonics.
Saturn
"Saturn" is the internal code name for the processor used in the
HP48, HP-28 series, and many other calculators (just about all
HP calculators since the HP 18/28 series).
STAR
This is the "Saturn Macro Assembler" (how "STAR" comes from
this, I don't know), an assembler that uses mostly Alonzo
Gariepy's mnemonics. It's written in C and runs on many
different machines (PCs, Amigas, Unix, etc.). STAR is available
via anonymous ftp from
<ftp://ftp.hp.com/pub/calculators/unix/star-1.04.4.tar.gz>
System RPL
This is the name for the custom "operating system/language" used
to program the CPU used in the HP48 calculator. System RPL is a
superset of the normal user RPL commands; in addition to the
normal, user-accessible RPL commands, system RPL includes many
lower-level functions. System RPL is a language one step higher
than assembly language.
HP has released a system development toolkit (for the IBM PC)
containing a system RPL compiler, assembler, and loader,
complete with a couple hundred pages of documentation. This
toolkit, while copyrighted, is, for the most part, freely
copyable. If you can find a BBS or archive site that has it,
you can download all of the system RPL files and documentation.
USRLIB
USRLIB is a program that takes the contents of an HP48 directory
and turns it into a library object. It currently runs under
MSDOS.
Voyager
Voyager is an "interactive disassembler" for IBM PC clones that
disassembles HP48 SX RPL and machine code. You download a copy
of the RAM and ROM in your HP48 SX to your PC, and run Voyager.
Using Voyager, you can then view the disassembled or unthreaded
code. Unfortunately (or fortunately), Voyager uses the HP
mnemonics, and not Alonzo Gariepy's mnemonics. Voyager is
available from the HP BBS <ftp://ftp.hp.com/pub/calculators/>,
and from various bulletin boards (the HP handhelds forum in
CompuServe also has a copy). The latest version is "1.07".
8.2. Is there a C compiler for the HP48?
Yes. Alex Ramos has written a GNU C back end for the Saturn
processor. Binaries are available for both Linux and Windows 95/NT,
and source is available for compilation on other platforms.
Check <http://www.cris.com/~ramos/hp48/hp48xgcc.htm> for the latest
version.
8.3. Why do SysRPL programs run faster than UserRPL programs?
SysRPL is the built in language, custom designed for the Saturn
processor used the HP48 family. UserRPL is a "subset" of SysRPL. The
main reason for the speed difference is the fact that UserRPL commands
have built in argument and error checking. In SysRPL, the programmer
is responsible for all error checking to avoid memory clears.
Note that System RPL is a compiled language and that therefore you
need a program like Jazz or GNU-Tools to create it. This means you
can't edit or view SysRPL on the HP48 directly, unlike UserRPL.
However both can be run the same way.
8.4. What is a good reference for learning SysRPL and ML?
Jim Donnelly's book "An Introduction to HP48 System RPL and Assembly
Language Programming" provides 230 pages of step by step instructions
for new programmers with plenty of examples. It also comes with a 3.5
inch disk containing the examples in source form and HP's development
tools for DOS. It was previously available from EduCalc, I'm not sure
if it is available elsewhere.
The ISBN number is: 1-879828-06-5
Also useful are RPLMAN.DOC and SASM.DOC available on Goodies Disk 4.
See Appendix E-5 for more information. You might want to also have a
look at the following URL: <http://titan.cs.uni-
bonn.de/~wolfrum/hpbooks.html>
Examples of ML programming can be found at:
o <http://www.geog.ubc.ca/~amoy/>
o <http://www.ite.mh.se/~danli97/>
8.5. Can I make my own libraries? Can I split others?
Yes, you can either use USRLIB in HP's development tools to create
libraries in DOS, or you can make them right on your HP with hacking
utilities like Rick Grevelle's D->LIB and L->DIR which can both create
and split libraries from/to directories. These can be found in Mika
Heiskanen's HACK library at <http://www.engr.uvic.ca/~aschoorl/>
8.6. How do I know what library ID number to use for my program?
Note: While this document says HP48 SX, it is also valid for GX.
HP48 SX Library ID Numbers Paul Swadener, HP Developer Support. 03
Sep 1993
The HP48 will become confused if two or more libraries currently in
the machine have the same ID numbers. To help third party developer
efforts, HP maintains a list of HP48 Allocated Library ID Numbers.
Below are the "rules." The penalty suffered from not following these
rules is that your library may not work if another library is in the
machine with the same number.
1. Don't use any number in the range 000h through 300h. These are
reserved for HP's use.
2. Don't use any number in the range 301h through 5A0h unless you have
been assigned that number by HP. These numbers are reserved for
developers who are in the business of distributing their software,
that is, Independent Software Developers.
To apply for the allocation of an ID# contact Paul Swadener,
Hewlett-Packard Company, 1000 NE Circle Blvd., Corvallis, OR 97330,
fax number 541-715-2192, internet address
paul_s...@hp6400.desk.hp.com. You must be a registered
developer and supply the name/nature of your product, and current
shipping address and phone/fax/internet add./etc.
3. Use a number in the range 5A1h through 600h for experimental work
and software. HP does not track the use of these numbers.
4. Use a number in the range 601h through 6F6h for your personal
applications, those which you will share, if at all, only to a
known set of other users for personal uses. HP does not track the
use of these numbers.
5. Don't use any number in the range 6F7 through 6FF, as these numbers
were allocated before the formal allocation process in was
instituted.
6. Don't use any number above 700h. These are also reserved for use by
HP.
Hope this helps clear up how library numbers work.
8.7. What information is there on the internals of the HP48?
The most important documents are part of the "System RPL" development
tools, a completely unsupported set of IBM PC tools created by HP
Corvallis (the creators of the HP48). The tools, which run on DOS
machines only, contain documentation on:
o System RPL (which includes information on HP48 SX display graphics,
keyboard control, etc.).
o Saturn assembly language ("Saturn" is the name of the CPU in the
HP48), including information on a Saturn assembler.
o A system RPL compiler.
o A Saturn object file linker.
However the documentation is also useful for some of the newer
program development tools such as Jazz and GNU-Tools. (See the
next question on where to obtain these).
8.8. Where can I get some programming development tools?
HP's unsupported System RPL development tools and documentation are
available to customers free of charge to help them in HP48 application
development, subject to certain legal terms, which are given with the
tools (they're too long and detailed to give here).
You can get a copy in one of the following ways:
o Anonymous ftp to <ftp://ftp.hp.com/pub/calculators/>
o Get Goodies Disk 4. For info, see Appendix E-5.
Alternatively, you can use one of the packages put together by
members of the HP community. In particular, Jazz is a library by
Mika Heiskanen which allows you to program in System RPL and
Machine Language directly on your HP48! It requires either an SX
with a RAM card, or a GX.
Jazz is available at <http://www.engr.uvic.ca/~aschoorl/>
There also is GNU-Tools by Mario Mikocevic (Mozgy) which is set of
replacements for HP's development tools that not only runs on DOS, but
also typical Unix systems such as Linux and Solaris. It is
distributed in both source and binary form.
GNU-Tools is available at:
o <ftp://gnjilux.cc.fer.hr/pub/hp48/gtools/>
o <http://www.zems.fer.hr/~mozgy/jwz/hp48.html>
8.9. I know UserRPL. How do I get started in SysRPL?
Here is a quick guide to learning System RPL. See the other questions
for more information on where to obtain the items below.
o Learn UserRPL first, and become familiar with most commands.
o Get Goodies Disk 4 (HPTOOLS) or GNU-Tools if you have Linux etc...
o Get the new release of supported entries, available with GNU-Tools
(not the entries in Goodies Disk 4).
o Read RPLMAN.DOC and/or get Jim's Donnelly book; it makes things
easier.
o Get ENTRIES.SRT from the HP48 IRC channel.
o Get the tables from the SAD package by ftp to
<ftp://ftp.hp.com/pub/calculators/>
o Get Jazz for your HP when you are ready.
o You can learn a lot by studying the ROM and other people's programs
with Jazz!
8.10. Are there any viruses for the HP48?
There are several, and most are French. In the United States, a virus
called the "Michigan virus" erupted a couple of years ago. There is a
program on Goodies Disk 8 that checks for the Michigan Virus.
Currently, viruses do not pose an appreciable threat on HP48's.
8.11. How do I store fields of variable length effectively?
See Appendix A-5 near the end of this file.
8.12. What is "Vectored Enter", and how do I use it?
From: Bill Wickes
The HP48 manuals do not document a very powerful feature that we call
"Vectored ENTER," that allows you in effect to redefine or bypass the
command line parser and to have a shot at the stack etc. after the
command line has been executed.
Keys that execute an automatic ENTER perform a two-step process:
1. The command line is parsed and evaluated.
2. The key definition is executed.
When flags -62 and -63 are both set, the system extends this
process as follows:
1. The current path is searched for a global variable named *aENTER
(where "*a" is the Greek alpha character--character 140). If
present, the command line is entered as a string object and *aENTER
is executed. If absent, the command line is parsed and evaluated
normally.
2. The key definition is executed.
3. The current path is searched for a global variable named *bENTER
("*b" is Greek beta--character 223). If present, then a string
representing the key definition is put on the stack, and *bENTER is
executed. The string is the key definition object's name if it is
a command, XLIB name, global or local name, or an empty string for
other object types; its primary purpose is to implement things like
the TRACE mode on other calcs, where you can print a running record
of what you do.
A simple example of the use of *aENTER is to create a more
convenient binary calculator, where *aENTER slaps a "#" on the
front of the command line so you don't have to bother when entering
numbers.
8.13. What is "WSLOG"?
It is an until recently undocumented feature which stands for "Warm
Start Log" (it is listed in the command appendix of newer G manuals,
as well as being fully explained in the AUR).
Type in WSLOG in caps, and calc will list the time and cause of the
last four warm starts. This feature helps HP technical support to fix
your HP48 in case it crashes.
0 - log cleared by <ON> <SPC> then <ON>
1 - low battery condition, auto deep sleep mode invoked to save battery
2 - hardware failed during IR (time out)
3 - run through address 0
4 - system time corrupt
5 - deep sleep mode wake up (alarm?)
6 - unused
7 - CMOS test word in RAM was corrupted
8 - abnormality was detected about device config
9 - corrupt alarm list
A - problem with RAM move
B - card module pulled
C - hardware reset
D - system RPL error handler not found in run stream
E - corrupt config table
F - system RAM card pulled
8.14. What are SYSEVALs?
SYSEVALs are addresses that point directly to a location in the HP48's
ROM. Many SYSEVAL hex strings are System-RPL commands. Because there
is no argument checking, it very easy to clear your HP48's memory.
In the file SYMBOLS.GX, HP designates three types of entries. The
first type is "supported." This means that a particular entry will
work on ALL versions of the HP48 and HP supports the use of this
entry.
The second type of entry is "unsupported." This means that HP does
not support the use of this entry and it will not be the same on all
versions of the HP48.
The third type is "unsupported-static." This is an entry to HP does
not support the use of, but it is the same for all versions.
8.15. What are some useful SYSEVALs?
For a complete list of supported entry points, see
<http://www.engr.uvic.ca/~aschoorl/>
In System-RPL, different HP object types are referred to by symbols.
These symbols are used to construct stack diagrams, which tell the
user how to use System-RPL commands. Here are some of the symbols:
Symbol Type Example
------ -------------------- -----------------
$ string "ABCDEFG"
id Global Name 'A'
arry Array [[ 1 2 ] [ 3 4 ]]
grob HP48 Graphics Object Graphic 131x64
# Binary Number <1h>
symb Symbolic Object 'A^2+B^2'
To interpret the stack diagram:
Everything on the left of the -> arrow is the input. That needs
to be on the stack before executing the SYSEVAL. The symbols
show you which kinds of data to put on the stack. Once you
execute the syseval (see next paragraph), the HP will return the
data back that is indicated on the right side of the arrow.
To use the following entries, do the following:
1. Make sure (triple check) that the appropriate arguments are
on the stack.
2. Push Right-shift /, you should get a # on the command line.
3. Enter the hex string exactly as shown in the hex string
column.
4. Put an small case h at the end of the hex string.
5. Press enter.
6. Type SYSEVAL.
Here are just a few examples:
Hex Sys-RPL Name Category Stack Diagram
--- ------------ -------- -------------
15777 NULLID Supported ( -> '' )
30794 VERSTRING Supported ( -> "HPHP48-?" )
3A328 MakeStdLabel Supported ( $ -> grob )
3A3EC MakeDirLabel Supported ( $ -> grob )
3A38A MakeBoxLabel Supported ( $ -> grob )
3A44E MakeInvLabel Supported ( $ -> grob )
3A1FC DispMenu.1 Supported ( -> )
05F42 GARBAGE Supported ( -> )
41F65 WaitForKey Supported ( -> #KeyCode #Plane )
353AB SYMB>IDS Unsupported-Static ( symb -> list )
40D25 LockAlpha Supported ( -> )
40D39 UnlockAlpha Supported ( -> )
3AA0A 1A/LockA Supported ( -> )
44C31 DoNewMatrix Supported ( -> arry )
44FE7 DoOldMatrix Supported ( arry -> arry' T/F )
1314D TOADISP Supported ( -> )
13135 TOGDISP Supported ( -> )
39531 ClrDA1IsStat Supported ( -> )
130AC RECLAIMDISP Supported ( -> )
4E347 TURNMENUON Supported ( -> )
05B15 $>ID Supported ( $ -> id )
05BE9 ID>$ Supported ( id -> $ )
3A1E8 DispMenu Supported ( -> )
39BAD DispStack Unsupported-Static ( -> )
8.16. What are LIBEVALs?
From: Joe Horn (Copied from "libeval.doc" on GD 9)
The G/GX has a new command: LIBEVAL. It's sort of like SYSEVAL, but
instead of taking a memory address (which could be ambiguous due to
the G/GX's massive need for bank switching), it takes XLIB numbers.
It's a "back door" for us hackers. Unlike the ELSYSEVAL command in
the HP Solve Equations Library Card, which only worked for the
libraries in that card, LIBEVAL works for any library, including the
hidden ones in the operating system.
CAUTION: LIBEVAL, like SYSEVAL, is both powerful and danger-
ous. If used with incorrect input(s) and/or in the wrong
environment, it can nuke your memory.
LIBEVAL takes a single user binary integer of the form #LLLFFFh, where
LLL is the library ID (hex), and FFF is the three-digit function num-
ber (hex, with leading zeros if necessary).
For example, the R->B command is XLIB 2 9. So you can perform a R->B
by executing #2009h LIBEVAL. Try it: 10 #2009h LIBEVAL -> #Ah.
Using it for named commands is unnecessary, but the G/GX is highly
XLIB oriented (again, due to the need for bank switching), and there
are many useful and interesting features accessible only through
LIBEVAL.
A prime example is the G/GX's inability to programmatically launch the
new "dialog boxes". Suppose a program needs to print things; it would
be awfully nice to be able to throw the I/O PRINT dialog box onto the
screen. The User's Guide is no help here, and in fact it would seem
impossible to do. But #B4197 LIBEVAL is all it takes! Try it. Cool,
huh?
8.17. What are some useful LIBEVALs? (GX)
See Appendix B-3 for a few GX LIBEVALs.
8.18. What is the format of a GROB object?
Note: I received two very good answers to this question, and each
cater to a different kind of user, so I will include them both.
The easy way:
First, add pixels to the right-hand edge to make the horizontal
dimension a multiple of 8, then separate the object horizontally
into groups of four pixels. Suppose, for example, you want to
make this into a 22x8 GROB:
---------****---------
--------**--**--------
-------**----**-------
********------********
********------********
-------**----**-------
--------**--**--------
---------****---------
You would break it up like this:
---- ---- -*** *--- ---- ----
---- ---- **-- **-- ---- ----
---- ---* *--- -**- ---- ----
**** **** ---- --** **** **--
**** **** ---- --** **** **--
---- ---* *--- -**- ---- ----
---- ---- **-- **-- ---- ----
---- ---- -*** *--- ---- ----
Notice, I've added two columns of pixels to make it 24x8. Now,
each group of four can be represented by a hexadecimal digit.
---- 0 --*- 4 ---* 8 --** C
*--- 1 *-*- 5 *--* 9 *-** D
-*-- 2 -**- 6 -*-* A -*** E
**-- 3 ***- 7 **-* B **** F
Now, replace each group of four pixels with its corresponding
hexadecimal digit: 00E100 003300 081600 FF0CF3 FF0CF3 081600
003300 00E100.
So, your final grob is:
GROB 22 8 00E100003300081600FF0CF3FF0CF308160000330000E100
The technical way:
1. Every HP object format is described in RPLMAN.DOC, see this
file for more info.
2. All HP objects are (of course) nibble based. When viewing
them on the PC, which is byte based, the low order nib is
always read and written first.
3. HP objects begin with a 5 nib prologue which identifies the
object type (and other things). This is the prologue for a
grob object..
02B1E pr HP:DOGROB
02B1E @ Graphic prologue (/U GROB)
4. Every 5 nib sub field of an object, such as prologue, length,
etc., is read in reverse order (low nib first). The grob
prologue would appear E1B20, or 1E 2B x0 in a hex dump on a
PC. The least significant nibble of the next field begins
right at the x in x0.
5. It is customary to always work with HP objects on the PC with
the HPHP48-E header (substitute your favourite rom version
letter) preceeding the prologue. This gives no hassles when
downloading via Kermit or X-Modem.
PC hex dump of a grob object.. ( remember each 5 nib field is
reverse order )
1. "HPHP48-E" 8 byte ascii string with msb off
2. 5 nib prologue, 02B1E (hex)
3. 5 nib length field, includes length of body AND length and
height fields! does not include 5 nib prologue. So, the
total #nibs the grob object takes in HP memory is this number
+ 5. Important!
4. 5 nib height field ( yes, it is height then width )
5. 5 nib width field
6. body (described below)
The grob object looking at it using command line EDIT on the
HP..
GROB <width (dec)> <height (dec)> < body >
The body is exactly the same looking at it on a PC hex dump or on
the command line EDIT. Just remember to read low nibble first for
hex dump.
Because of hardware restrictions, the number of nibs required to
represent one horizontal line must be even (byte aligned). So, use
this method to calculate the number of nibs in one line.. (pascal
example)
nibs := width div 4;
if nibs mod 4 <> 0 then nibs := nibs + 1;
if odd(nibs) then nibs := nibs + 1;
Then to get the #nibs in the entire body, multiply it by the
height. Remember, the length field must be this total body length
+ 15 !
For example, a 131 wide grob requires 34 nibs for one horizontal
line, where 5 of the bits are unused. The first nib in the second
line begins at nib 35 for this grob, etc... If the grob is 64
lines, then the body is 2176 nibs. Add 5 for the prologue, 5 for
the length field, 5 for height, and 5 for width. Total object size
(on the HP) is 2196 nibs, or 1098 bytes. The length field should
contain 2196 minus 5 for prologue = 2191 (0088F hex)
Note that for each nib, the right-most bit is the left-most pixel
on the screen. This is nearly always the case for graphic memory.
8.19. What is the AUR and what information does it contain?
From: Jarno Peschier <jpes...@cs.ruu.nl>
In this text I will try to answer a number of frequently asked
questions about the HP48 G Series Advanced User's Reference Manual.
In the remainder of this text I will use the common abbreviation AUR
when referring to this book.
A good link for AUR information is at:
<http://www.contrib.andrew.cmu.edu/~drury/hp48gaur/>
The questions I will try to answer are:
o What is the AUR?
o What information does the AUR contain?
o Do I need the AUR?
o Why didn't HP supply the AUR with every HP48?
o Where can I get the AUR?
o Does the AUR contain any SYSEVALs and/or LIBEVALs?
o Does the AUR say anything about SysRPL and/or ML?
What is the AUR?
The AUR is just what it's name tells you it is: it's a reference
manual for the HP48 G Series. It has the same outside
appearance as the HP48 G Series User Guide (the manual you get
with your HP48 G or HP48 GX when you buy it), except that it's
much thicker (just under 4 cm). The AUR contains about 650
pages of useful information about your calculator.
What information does the AUR contain?
The AUR contains information about UserRPL programming, quite a
lot of programming examples, a complete command reference for
all the (UserRPL) commands the G Series knows and reference
lists about all equations, error and status messages, units,
etc... Of course it has an extensive index at the back of the
book.
Chapter 1: Programming
Contains: Understanding Programming, Entering and Executing
Programs, Viewing and Editing Programs, Creating Programs on
a Computer, Using Local Variables, Using Tests and
Conditional Structures, Using Loop Structures, Using Flags,
Using Subroutines, Single-Stepping through a Program,
Trapping Errors, Input, Stopping a Program for Keystroke
Input, Output, Using Menus with Programs, Turning Off the
HP48 from a Program.
Chapter 2: Programming Examples
Contains: Fibonacci Numbers, Displaying a Binary Integer,
Median of Statistics Data, Expanding and Collecting
Completely, Minimum and Maximum Array Elements, Applying a
Program to an Array, Converting Between Number Bases,
Verifying Program Arguments, Converting Procedures from
Algebraic to RPN, Bessel Functions, Animation of Successive
Taylor's Polynomials, Programmatic Use of Statistics and
Plotting, Trace Mode, Inverse-Function Solver, Animating a
Graphical Image.
Chapter 3: Command Reference
This chapter contains one entry for every command (except for
RULES) from ABS to ZVOL and + to ->. Each entry contains:
o A description of what the command does (with stack diagrams).
o Ways in which you can access it from the keyboard (with
submenu you need, or if you can only type it in in Alpha-
mode).
o Which flags the command is affected by.
o Remarks, and a list of related commands.
Often a command has one or more example programs too. This
chapter is the bulk of the whole book; it's 424 pages thick.
Chapter 4: Equation Reference
This chapter contains one entry for every section in the
built in Equation Library (EQLIB). Each entry contains: a
table of used variables and then for every set of equations
an entry with some more info about the equation set, the
picture that goes with it (if any), all the equations and one
or more sets of example numbers and solutions. The end of
the chapter has a list of references from which all the
equations were taken.
Appendix A: Error and Status Messages
This chapter contains two tables with all possible messages.
The first has them sorted alphabetically and shows the
message, the meaning and the ERRN number in hex. The second
has them sorted on ERRN number (and thus on category) and
only contains the number in hex and the message itself.
Appendix B: Table of Units
This chapter contains a table with all units the HP48 G
Series knows. It contains the unit (both the name you use on
the calculator as well as the full name) and the value it
represents in SI units.
Appendix C: System Flags
This chapter contains a table with all the system flags of
the HP48 G Series. The table contains the number followed by
a description of it's use and the results you get when the
flag is set or clear.
Appendix D: Reserved Variables
This chapter contains a table with all the reserved variables
of the HP48 G Series (ALRMDAT, CST, "der"-names, EQ, EXPR,
IOPAR, MHpar, Mpar, n1/n2/..., Nmines, PPAR, PRTPAR,
s1/s2/..., VPAR, ZPAR, SigmaDAT and SigmaPAR) with complete
information about what they are used for and about all
possible parameters that can be put into them.
Appendix E: New Commands
This chapter lists all the commands that are new to the HP48
G Series, with a brief description of what the commands do.
A list like this can be found elsewhere in the HP48 FAQ list
as well.
Appendix F: Technical Reference
Contains: Object sizes, Mathematical simplification rules
used by the HP48, Symbolic differentiation patterns used by
the HP48, the EquationWriter's expansion rules, References
used as sources for constants and equations in the HP48
(other than those in the Equation Library).
Appendix G: Parallel Processing with Lists
This chapter contains info on parallel processing that makes
UserRPL look even more like a real functional programming
language by letting (almost) all the commands function on
lists of parameters as well (i.e. adding map capabilities to
all internal commands).
Do I need the AUR?
Yes, you do. In my humble opinion the AUR is just "The Manual,
Part II" and every owner of a HP48 G or HP48 GX should have it,
especially if you are (going to be) programming in UserRPL for
any reason. A lot of the frequently asked questions that pop up
on comp.sys.hp48 are simply questions that are meant to be
answered by the AUR.
Why didn't HP supply the AUR with every HP48?
Since you're reading this FAQ, you're probably gifted: you are
not an average HP48 user. The set of "average users" probably
consists mostly of people that simply never program their HP48
in any way ("Wow, can it do that too?!"). In this case, they
will never take one look at the AUR ever again, and since this
is quite a thick book it would be a waste of money, trees, the
environment, transportation costs, etc... to supply the AUR in
every box. This is probably why HP made it an extra accessory
for those people that "really need" it. I think...
Where can I get the AUR?
You should be able to buy (or order) it from the same shop where
you purchased your calculator. The HP part number is
00048-90136. The book does not seem to have an ISBN; it's a HP
part, not a book.
Does the AUR contain any SYSEVALs or LIBEVALs?
Yes, it contains exactly one. The example for the SYSEVAL
command tells you that #30794h SYSEVAL gives you the version of
your HP48. My HP48 GX rev. P gives "HPHP48-P".
Does the AUR say anything about SysRPL or ML?
No, it doesn't.
8.20. What is the syntax for INFORM, CHOOSE, and MSGBOX? (GX)
Based on a posting on HPCVBBS by Cary McCallister. Revised by Joe
Horn. Re-formatted by Andre Schoorl.
INFORM - Create a Custom Input Form
INPUT:
5: "title"
4: { fields }
3: <format>
2: { reset_values }
1: { initial_values }
OUTPUT:
Either: 2: { new_values }
1: 1
or: 1: 0
PURPOSE:
INFORM creates full-screen custom input forms, similar to
those of the built-in applications.
ARGUMENTS:
title
Is displayed in font 1 (small) at the top centre of the
screen. It may contain any number of characters,
including 0, but, at most, 31 characters will be
displayed. Strings longer than 31 character will be
truncated to 30 characters and displayed with a trailing
ellipsis. Line feed characters are displayed as boxes.
{ fields }
Is a list of the form { field1 field2 ... fieldn } where
each field is any one of these forms:
1. "label"
2. { "label" "help" }
3. { "label" "help" type1 type2 ... typen }
4. { }
The "label" is a string of arbitrary text from 0 to 26 char-
acters long (longer strings will be truncated to 25 charac-
ters with a trailing ellipsis). The "help" is displayed
immediately above the menu area as a helpful prompt for the
user. The object type specifications list the one or more
object types allowed in the field, in the form the TYPE com-
mand returns. If unspecified, the default help text is blank
and the field will accept all object types. If a field spec-
ification is an empty list, no field is produced; instead,
the field to the immediate left (if any) is expanded to fill
the omitted field's space. This allows further customization
of form layout; for example, to have two fields in one row
and three fields in the next.
<format>
May be any one of the following objects:
1. { }
2. columns
3. { columns }
4. { columns widths }
Where <columns> is the number of columns that the display
will be divided into e.g., if <columns> is 2 and there are
two fields, they will be displayed side by side rather than
one above the other. <widths> is the tab width between the
left edge of each title and its field; this makes vertical
alignment of fields possible. Titles longer than one tab
width will cause the tab to be repeated automatically. If
unspecified, the default column count is one and the default
tab stop width is three.
{ reset_values }
Is a list of values one per input field which replace the
values of all fields when the {RESET} key is pressed and
"Reset all" is selected. This list must either be empty
or have exactly one item per field corresponding to the {
fields } list above. If empty, then all fields are deemed
unspecified (i.e., blank). Each reset value must match
the type require by the form field. Selected fields may be
marked as unspecified by using NOVAL as the reset value.
{ initial_values }
is a list of values one per input field which specify the
start-up values of all fields when the INFORM command is
invoked. This list must either be empty or have exactly
one item per field corresponding to the { fields } list
above. If empty, then all fields are deemed unspecified
(i.e., blank). Each initial value must match the type
require by the form field. Selected fields may be marked
as unspecified by using NOVAL as the initial value.
RESULTS:
INFORM returns the new field values { new_values } as a list
to level 2 and the real value 1 to level 1 if the user
completes the input form by pressing {OK} or [ENTER]. The
list will contain one item per field. Each item will either
be the last input value for the corresponding field, or NOVAL
if the field was unspecified.
INFORM returns the real value 0 to level 1 if the user
terminates the input form by pressing {CANCL} or [CANCEL].
REMARKS:
NOVAL is basically a command (an XLIB name) that does nothing
when evaluated. It can, however, be compared via ==, SAME and
POS.
CHOOSE - Create a User-Defined Choose-Box
INPUT:
3: "title"
2: { items }
1: <initial_item_number>
OUTPUT:
Either: 2: { chosen_item }
1: 1
or: 1: 0
PURPOSE:
CHOOSE creates a user-defined "choose-box": a displayed box
containing items from which the user can choose one.
CHOOSE displays a standard choose box (normal, not maximized;
single-pick, not multi-pick) with an optional title line.
ARGUMENTS:
title
If any, is displayed in font 1 (small) in the top centre
of the box. It may contain any number of characters,
including 0, but, at most, 22 characters will be
displayed. Strings longer than 22 character will be
truncated to 21 characters and displayed with a trailing
ellipsis. Line feed characters are displayed as boxes.
If there are more than four items such that the scroll
arrows are displayed, the maximum number of title
characters is reduced to 21. The title text is displayed
in the title area in character font 1 (the menu font). If
the title string is empty, no title area will be created
in the choose box, and the whole box will be devoted to
the items.
{ items }
Is a list of arbitrary objects. Each item occupies one
line in the choose box and is displayed in its command
line form. Only the first 14 characters of the displayed
object will be shown (13 if the scroll arrows are
present). If an item contains more than 14 (13)
characters, it will be truncated to 13 (12) and the final
character will be replaced by an ellipsis. If every item
is a list of exactly two objects, the first object will be
displayed and the second returned if the item is selected.
If the number of items exceeds 4 with a title and 5
without, scroll arrows will be displayed, and moving the
highlight past the top or bottom of the box will scroll
through the undisplayed items.
<initial_item_number>
Specifies the initial field to be highlighted when the
display first comes up (ordinarily 1). A value of 0
indicates that no field is to be highlighted and that the
{CANCL} key is to be omitted from the menu, making the
choose box act as an informational display without user
selection.
RESULTS:
CHOOSE returns the chosen item (or the second object in a
two-element item list) and the real number 1 if the user
completes the choose box by pressing {OK} or [ENTER]. CHOOSE
returns the real number 0 if the user terminates the choose
box by pressing {CANCL} or [CANCEL].
MSGBOX - Create a Simple Message Box
INPUT:
1: "Message_string"
OUTPUT:
None
PURPOSE:
MSGBOX creates a simple pop-up message box over the current
display, with a 3D shadow to make it easy to recognize, and
containing any arbitrary text.
ARGUMENTS:
Message_string
Is any string of characters. The text is displayed in
font 2 (medium size), left justified, with a maximum line
length of 15 characters. Longer lines are broken into
multiple lines automatically, at word breaks when
possible, up to a maximum of 5 lines. Line feeds may be
included to force line breaks. The minimum number of
lines is 2, so single-line messages will have a blank line
at the bottom of the box.
RESULTS:
None. MSGBOX is exited when the user presses CANCEL, ENTER,
or OK, but nothing is returned to the stack.
For examples of INFORM, CHOOSE, and MSGBOX see Appendix B-2.
8.21. How do I put checkfields in my INFORM menus?
From: Matt Willis
You can't normally do this directly in User RPL. You can do it in
System RPL (see Jim Donnelly's book for details), or you can use the
library at <http://www.hpcalc.org/programming/misc/infm2v1.zip>
I figured that the System RPL version of DoInputForm was unpleasant
enough to use on a casual basis so I wrote a simple library that lets
you use check boxes and choose lists from User RPL.
All it does is stop execution of INFORM just before DoInputForm, then
search the stack and change object types to check and choose objects.
Then it restarts the INFORM command. At the end, it tidies up
TRUE/FALSE to 1/0 etc...
Example syntax:
"Test" {
"A" "B" "C" } 1 {} { :CHECK: 1 :CHOOSE: { 1 2 3 } NOVAL }
IF INFORM2 THEN
...insert code here...
END
8.22. What is the syntax for the INPUT command?
From: John Meyers
INPUT allows you to display a message and then edit a given string
using the command line editor; the edited string is its result.
Arguments:
Level 2:
"message"
The message is displayed in "medium font" in the upper part of
the "stack display area" (the stack itself is not visible during
the INPUT command). The message may be an empty string, or may
contain newlines for a multiple-line message.
Level 1:
The most general format is a non-empty list containing up to
three optional specifications, which may appear in any order:
{ "string" { row column } mode(s) }
"String" is the initial text which will appear in the command
line; it may be an empty string, or may contain newlines for a
multiple- line text. If you do not need to specify any other of
the optional arguments, you may omit the list itself and supply
only the string on level 1. If the string is omitted from an
argument list, the default is an empty string.
Mode(s) are zero or more of the following special reserved
names:
o Type a Greek Alpha symbol (Alpha right-shift A) to start the
editor with Alpha keyboard mode on.
You might select this mode if you are inviting the user to type
general text; you would not type quotation marks around the
entered text, because INPUT automatically returns as a string
all the characters that are typed into the edit line.
o The word ALG starts the editor in Algebraic entry mode (ALG
annunciator on); PRG mode is always on by default.
o The letter V will check the syntax of the entire command line
when ENTER is finally pressed, in exactly the same way that the
command line editor normally does, disallowing an exit if there
is an RPL syntax error. However, unlike ordinary editing in the
command line, the command line text is still returned as a
string, and is not compiled for you (you can do OBJ-> yourself
afterwards if you want to compile the string).
For example, if you are expecting two numeric values to be
entered, and if you enter 123 456, INPUT returns "123 456"; if
you then do OBJ-> on that result, you will finally get 123 and
456 as separate values on the stack.
Row and Column optionally specify where the cursor will
initially appear (default is at the end of the entire string),
and whether the cursor will start in "insert" or "replace" mode
(default is insert).
Row numbers start at 1 for the topmost row; column numbers start
at 1 for the first character in a row. Row zero means the
bottom row; column zero means the end of a row.
Instead of { row column } you may also simply count character
positions within the original "string" argument, supplying just
one number instead of a list of two numbers.
To cause the cursor to be in "replace" mode rather than "insert"
mode, the first number specifying cursor position should be made
negative.
If the user presses CANCEL during INPUT when there is some text in the
command line, all the text will be erased without canceling INPUT; if
CANCEL is pressed again (or with no text), then INPUT is canceled.
Examples of use in a program:
"Enter A, B, C" {
":A:
:B:
:C:" { 1 0 } V } INPUT
Note: Put newlines between the three lines of the initial string.
When executed, the screen shows:
Enter A, B, C
:A:(cursor appears here)
:B:
:C:
If you now press 1 DownArrow 2 DownArrow 3 ENTER, the string returned
on the stack is:
":A:1
:B:2
:C:3"
If you then do OBJ-> on this string, you get (on separate stack
levels):
:A: 1
:B: 2
:C: 3
The optional "tags" do not interfere with using the numeric values in
functions, or storing them (tags are automatically removed in each
case).
Another example:
"Type a new notecard" { Alpha-symbol } INPUT
This allows the user to type any free-form text, which is returned as
a string upon pressing ENTER.
Simplest possible example:
"" "" INPUT (no message, empty initial command line)
Potential problems with INPUT (if OBJ-> is to be used afterwards to
get the values entered):
o You can't force the user to enter the exact number of values
expected, so you may want to program defensively (check stack
depth, etc...)
o Entries such as command names (e.g. CLVAR), program names, etc...
will get executed by a subsequent OBJ->, producing undesirable
effects (methods for dealing with this problem are available).
For applications expecting non-text values to be entered, the HP48G/GX
INFORM command is more immune to these problems, and affords much
tighter control over what is entered, in addition to providing a more
beautified display form, a separate prompt for each input field, etc.
The syntax for INFORM is detailed elsewhere in the FAQ.
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