Amiga 1000 seems dead -- help w/ hardware?
ToasterKing
of you die-hard Amiga techies could help someone with next to no
knowledge of Amiga hardware with a hardware problem! =)
The unit is an Amiga 1000 (yep, an oldie!). The mainboard is REV 6,
and bears the printed number 327049-01.
Any additional hardware:
A 1 MB memory expansion module in the cartridge port.
Symptoms:
Won't boot, no video, no floppy access, nada.
(By the way, I don't have a proper RGB adapter or the RF modulator, so
I'm using the composite video output for testing.)
I've checked:
The power supply voltages - OK
Shorts in power supply on board and connectors - none (OK)
+5V anywhere I think it should be - OK
IC sockets and connectors - OK
(Unfortunately, I don't have enough knowledge to verify much more than
the power supply on this one.)
Other troubleshooting measures:
-Removed memory module from cartridge port - still nothing.
-Removed floppy drive - still nothing.
-There's a large piggyback board residing on top of the mainboard,
kinda shaped like a letter "Z", with no decipherable label. Lots of
small ICs on it, mostly PALs and complex logic gates. Not sure what
this does, or if it was an option or standard hardware, but I removed
it, and still nothing.
What could be wrong with it? I am familiar with the OS, but as is
apparent, know next to nothing about the hardware.
I DID notice that there are two EPROMs on the mainboard:
-One is labeled on the board as "U5N" and "EVEN", with the label on the
chip "252179-01, REV.11"
-The other is labeled on the board as "U5P" and "ODD", with the label
on the chip "252180-01, REV.11"
These chips are at board positions 5N and 5P, respectively.
I'm considering these a definite possibility, considering an EPROM's
potential for data leakage from ultraviolet light and all that junk.
Can someone tell me what these EPROMs do, and if there's a current
source for replacemens for them? I wish I had an EPROM burner, but I
don't. Is this a common source of problems in this old hardware?
Any sources of other replacement parts for the unit's future
longetivity are also happily welcomed, as I have nada!! I can repair
or replace the power supply, minor things like connectors, even have
old Mac Pluses I could pull a 68000 out of, but nothing else!
If someone could direct me to a group FAQ, I'd also appreciate it.
By the way, this unit was given to me by a friend who claims it just
wouldn't boot one day, and he didn't see the point in repairing or
replacing it. It was running perfectly the day before. Sounds like it
could be an EPROM.
Thank you!!!
--
I'm only human. Corrections to any technical info I give are welcome.
<<Please remove the word "SPLAT" from either below address to use it.>>
Email: mailto:Toast...@SPLATmindless.com
Visit ToasterKingdom at http://SPLATtoasterking.tripod.com/
Clockmeister
ToasterKing wrote in message
<210320010313441934%Toast...@SPLATmindless.com>...
>Hi there! This is my first-ever post in this group. I wonder if some
>of you die-hard Amiga techies could help someone with next to no
>knowledge of Amiga hardware with a hardware problem! =)
>
>The unit is an Amiga 1000 (yep, an oldie!). The mainboard is REV 6,
>and bears the printed number 327049-01.
>
>Any additional hardware:
>A 1 MB memory expansion module in the cartridge port.
If it's the front exram connector you mean (and not the side one) it's a
256K expansion card to bring the A1000 to 512kb up to 512k total chipRAM.
The A1000 should work just fine with it removed.
>
>Symptoms:
>Won't boot, no video, no floppy access, nada.
>(By the way, I don't have a proper RGB adapter or the RF modulator, so
>I'm using the composite video output for testing.)
Does the power LED light up, and if it does - does it flash at all?
>
>I've checked:
>The power supply voltages - OK
>Shorts in power supply on board and connectors - none (OK)
>+5V anywhere I think it should be - OK
>IC sockets and connectors - OK
>(Unfortunately, I don't have enough knowledge to verify much more than
>the power supply on this one.)
What did you check the power supply against? (where did you get the voltage
info from?)
>
>Other troubleshooting measures:
>-Removed memory module from cartridge port - still nothing.
>-Removed floppy drive - still nothing.
>-There's a large piggyback board residing on top of the mainboard,
>kinda shaped like a letter "Z", with no decipherable label. Lots of
>small ICs on it, mostly PALs and complex logic gates. Not sure what
>this does, or if it was an option or standard hardware, but I removed
>it, and still nothing.
That's the daughterboard and should remain plugged in for the A1000 to work
at all.
>
>What could be wrong with it? I am familiar with the OS, but as is
>apparent, know next to nothing about the hardware.
>I DID notice that there are two EPROMs on the mainboard:
>-One is labeled on the board as "U5N" and "EVEN", with the label on the
>chip "252179-01, REV.11"
>-The other is labeled on the board as "U5P" and "ODD", with the label
>on the chip "252180-01, REV.11"
>These chips are at board positions 5N and 5P, respectively.
>I'm considering these a definite possibility, considering an EPROM's
>potential for data leakage from ultraviolet light and all that junk.
>Can someone tell me what these EPROMs do, and if there's a current
>source for replacemens for them? I wish I had an EPROM burner, but I
>don't. Is this a common source of problems in this old hardware?
No, not a common problem, and those ROM's are the kickROM's which contain
enough code to boot the kickstart disk (disk based ROM) and a small startup
tune and screen.
>
>Any sources of other replacement parts for the unit's future
>longetivity are also happily welcomed, as I have nada!! I can repair
>or replace the power supply, minor things like connectors, even have
>old Mac Pluses I could pull a 68000 out of, but nothing else!
>If someone could direct me to a group FAQ, I'd also appreciate it.
>
>By the way, this unit was given to me by a friend who claims it just
>wouldn't boot one day, and he didn't see the point in repairing or
>replacing it. It was running perfectly the day before. Sounds like it
>could be an EPROM.
>
Try reseating all socketed chips on the motherboard and check to see if the
68000 is getting warm. If not, put another in it's place.
BTW, a dead clock crystal (under the little tin cover) will cause a sympton
like this also...
See my page for some A1000 stuff and usefull links ;-)
Regards,
Clockmeister.
Justin
in various condition in my hands not too long ago, but sold them on ebay. I
could put you in touch with the buyer if you are interested - please email
me directly if you want to do that.
Thanks,
Justin
hemm...@cyberus.ca
"ToasterKing" <Toast...@SPLATmindless.com> wrote in message
news:210320010313441934%Toast...@SPLATmindless.com...
ToasterKing
<hemm...@cyberus.ca> wrote:
>If the MB is dead, one should be easily found for not too much $$. I had 10
>in various condition in my hands not too long ago, but sold them on ebay. I
>could put you in touch with the buyer if you are interested - please email
>me directly if you want to do that.
That's an attractive option, pricewise, but I'd rather try to fix this
one first -- just the thrill of the challenge, ya know? =) Besides, I
think I've narrowed the problem down to the power supply unit now.
Thank you for your offer though!!!
ToasterKing
doing, unlike me! ;-)
It seems my power supply diagnosis was done a little hastily. Upon
further examination tonight, it seems that may be the only problem. If
you have pinouts/proper voltages on-hand, I'd appreciate you verifying
this!! More responses interepersed below...
In article <Jjou6.37$gv6....@nsw.nnrp.telstra.net>, "Clockmeister"
<gerr...@tnet.com.au> wrote:
>If it's the front exram connector you mean (and not the side one) it's a
>256K expansion card to bring the A1000 to 512kb up to 512k total chipRAM.
>The A1000 should work just fine with it removed.
You're correct -- it's the front one. And about the expansion card,
right again. It is indeed 256K, not 1024K. It seems I did this whole
diagnosis a little hastily! For some reason, I read the "256 X 4"
printed on the card's PCB as being a total of 1024 MB -- I like to
think that I'm not usually that absent-minded, but there ya go, heehee.
=)
>Does the power LED light up, and if it does - does it flash at all?
The power LED does light up, and glows its usual steady red. It
doesn't flash or even flicker. I don't know much about the in the
Amiga's power management logic, but this tells me that at least the +5V
for logic is good... I'd like more information on this little
bnlinking phenomenon too if you don't mind giving it -- I want to learn
all about this great machine I can! Power supply comments below...
>What did you check the power supply against? (where did you get the voltage
>info from?)
I did many searches on the Web looking for the pinout, but after not
finding it after about 25 minutes, I decided to check it without them
-- I relied considerably on guesswork. =) What I did was identify the
ground wire, trace the +12V and +5V connections from the floppy power
connector with an ohmmeter, and just assume the other two were -5V and
-12V, as is pretty much the standard.
I tested the supply when connected to the mainboard, and also tested it
while disconnected -- voltages were stable both ways. I found
something tonight I had somehow missed earlier when testing the supply.
The grey wire at the far end of the connector is only reading +3.3
Volts. I'm assuming it's supposed to be -12 Volts DC. Can you verify
this?? Also, the transistor at Q40 in the power supply case is getting
MUCH hotter than it should -- just hovering my hand over it but not
touching it, it feels very hot. This transistor is connected to an
aluminum heatsink. It seems there's a short somewhere in the PSU.
Here are the readings I got -- please verify them if you can. If you
can verify that the grey wire should be -12V, I can wire in another PSU
and see if it works. If it does, then I'm fairly sure I can repair the
Amiga's stock PSU with no difficulty (I could just put another in, but
it wouldn't fit right!).
I'm not sure of the pin numbers (which end is 7 and which is 1), so
these are going in order across the connector, and identified by
colour...
Colour | Test Voltage
=====================
Violet -5V
Orange +12V
Black Ground
Black Ground
Red +5V
Red +5V
Grey +3.3V (should be -12V???)
>That's the daughterboard and should remain plugged in for the A1000 to work
>at all.
I stripped everything else off first, then when it still did not work,
I tried removing the daughterboard. So ya, I did test it once with the
daughterboard connected but nothing else.
>No, not a common problem, and those ROM's are the kickROM's which contain
>enough code to boot the kickstart disk (disk based ROM) and a small startup
>tune and screen.
Thanks for the info! I've known some specific hardware that was known
for EPROMs to fail in, but that was the manufacturer's stupid mistake
-- white paper labels were put over the EPROM package's window instead
of foil labels that really keep the ultraviolet light out. I've also
seen some with no labels. The foil ones really do help prolong them.
>Try reseating all socketed chips on the motherboard and check to see if the
>68000 is getting warm. If not, put another in it's place.
>BTW, a dead clock crystal (under the little tin cover) will cause a sympton
>like this also...
I've tried reseating socketed chips many times, believe me! It looks
like the power supply is the problem, but I'll make note of the clock
crystal -- could come in handy later. Are these full-size TTL
oscillators known to fail in these machines?
>See my page for some A1000 stuff and usefull links ;-)
>
>www.tnet.com.au/~gerryvdb
I took a look -- you give a lot of useful info! Thanks for the tips
and the advice... and have a good day! =)
Toasty
P.S. By the way, do you know what the Amiga 1000's power consumption
(in Watts) is like? And how high does this escalate, the more cards
that are added?
Clockmeister
ToasterKing wrote in message
<230320012240490201%Toast...@SPLATmindless.com>...
>Hey, Clockmeister! SO nice to hear from someone who knows what he's
>doing, unlike me! ;-)
Nice to be greeted with such an enthusiastic response ;-)
>It seems my power supply diagnosis was done a little hastily. Upon
>further examination tonight, it seems that may be the only problem. If
>you have pinouts/proper voltages on-hand, I'd appreciate you verifying
>this!!
I'll check these for you as I don't have them on hand, but I do have a
couple of working A1000's here.
More responses interepersed below...
>
>In article <Jjou6.37$gv6....@nsw.nnrp.telstra.net>, "Clockmeister"
><gerr...@tnet.com.au> wrote:
>
>>If it's the front exram connector you mean (and not the side one) it's a
>>256K expansion card to bring the A1000 to 512kb up to 512k total chipRAM.
>>The A1000 should work just fine with it removed.
>
>You're correct -- it's the front one. And about the expansion card,
>right again. It is indeed 256K, not 1024K. It seems I did this whole
>diagnosis a little hastily! For some reason, I read the "256 X 4"
>printed on the card's PCB as being a total of 1024 MB -- I like to
>think that I'm not usually that absent-minded, but there ya go, heehee.
>=)
>
>>Does the power LED light up, and if it does - does it flash at all?
>
>The power LED does light up, and glows its usual steady red. It
>doesn't flash or even flicker. I don't know much about the in the
>Amiga's power management logic, but this tells me that at least the +5V
>for logic is good... I'd like more information on this little
>bnlinking phenomenon too if you don't mind giving it -- I want to learn
>all about this great machine I can! Power supply comments below...
Yep, sounds like you have 5v there. The blinking phenomenon is basically
what the A1000 does when it tries to do a reset and goes through a
diagnostic procedure, or when the GURU has been for a visit and the system
has crashed.
Doing a CTRL-AMIGA-AMIGA keyboard combo should show the LED flashing as the
A1000 goes through the reset... if it doesn't the A1000 is effectively not
initializing at all.
To see if the Amiga is working at all, disconnect the drive cable and power
connector to the internal drive (just to eliminate the possibility of a
shorted drive). Switch the Amiga on whilst keeping an eye on the LED. It
should start up at half brightness and then change to full illumination
after a short period of time. Does yours do that much?
>>What did you check the power supply against? (where did you get the
voltage
>>info from?)
>
>I did many searches on the Web looking for the pinout, but after not
>finding it after about 25 minutes, I decided to check it without them
>-- I relied considerably on guesswork. =) What I did was identify the
>ground wire, trace the +12V and +5V connections from the floppy power
>connector with an ohmmeter, and just assume the other two were -5V and
>-12V, as is pretty much the standard.
>
>I tested the supply when connected to the mainboard, and also tested it
>while disconnected -- voltages were stable both ways. I found
>something tonight I had somehow missed earlier when testing the supply.
>The grey wire at the far end of the connector is only reading +3.3
>Volts. I'm assuming it's supposed to be -12 Volts DC. Can you verify
>this?? Also, the transistor at Q40 in the power supply case is getting
>MUCH hotter than it should -- just hovering my hand over it but not
>touching it, it feels very hot. This transistor is connected to an
>aluminum heatsink. It seems there's a short somewhere in the PSU.
Or on the motherboard?
>Here are the readings I got -- please verify them if you can. If you
>can verify that the grey wire should be -12V, I can wire in another PSU
>and see if it works. If it does, then I'm fairly sure I can repair the
>Amiga's stock PSU with no difficulty (I could just put another in, but
>it wouldn't fit right!).
>
>I'm not sure of the pin numbers (which end is 7 and which is 1), so
>these are going in order across the connector, and identified by
>colour...
Ok, I'll fill in the voltages that I get on one of my A1000's. (They should
be checked with the PSU connector plugged onto the motherboard, grey wire to
the rear of the computer)
>Colour | Test Voltage
>=====================
>Violet -5V -5.15V
>Orange +12V +12.12V
>Black Ground
>Black Ground
>Red +5V +5.03V
>Red +5V +5.03V
>Grey +3.3V (should be -12V???) +2.74V
Your voltage readings seem pretty normal. After having my A1000 on for a few
minutes, all the custom chips, RAM chips and CPU are warm to the touch. If
any of those chips in your A1000 are very hot or cold, I'd try starting
there.
Also make sure that your ground lines are actually grounded (check between
black wires on the connector and the PSU housing) and the internal drive
connectors are fitted the right way around also.
>
>>That's the daughterboard and should remain plugged in for the A1000 to
work
>>at all.
>
>I stripped everything else off first, then when it still did not work,
>I tried removing the daughterboard. So ya, I did test it once with the
>daughterboard connected but nothing else.
That's OK, you won't damage anything by doing that.
>>No, not a common problem, and those ROM's are the kickROM's which contain
>>enough code to boot the kickstart disk (disk based ROM) and a small
startup
>>tune and screen.
>
>Thanks for the info! I've known some specific hardware that was known
>for EPROMs to fail in, but that was the manufacturer's stupid mistake
>-- white paper labels were put over the EPROM package's window instead
>of foil labels that really keep the ultraviolet light out. I've also
>seen some with no labels. The foil ones really do help prolong them.
Have you tried swapping them over? (It won't damage them)
>>Try reseating all socketed chips on the motherboard and check to see if
the
>>68000 is getting warm. If not, put another in it's place.
>>BTW, a dead clock crystal (under the little tin cover) will cause a
sympton
>>like this also...
>
>I've tried reseating socketed chips many times, believe me! It looks
>like the power supply is the problem, but I'll make note of the clock
>crystal -- could come in handy later. Are these full-size TTL
>oscillators known to fail in these machines?
No, not a common fault by any means but I've had one dead A500 with that
problem.
The CPU remains cold to touch if the oscillator doesn't work, assuming that
the CPU is OK ofcourse.
>
>>See my page for some A1000 stuff and usefull links ;-)
>>
>>www.tnet.com.au/~gerryvdb
>
>I took a look -- you give a lot of useful info! Thanks for the tips
>and the advice... and have a good day! =)
>
>Toasty
>
>P.S. By the way, do you know what the Amiga 1000's power consumption
>(in Watts) is like? And how high does this escalate, the more cards
>that are added?
>
The A1000 supply is rated about 60W from my calculations, and that doesn't
leave much of a margin for expansion cards. With an additional RAM card, a
HDD controller and an external floppy drive the supply would soon reach it's
limit I would think.
Regards,
Clockmeister.
*** www.tnet.com.au/~gerryvdb ***
ToasterKing
This A1000 is pissing me off, LOL!
Okay, so we'll assume it's not a power supply problem. Thank you for
verifying those voltages!!!
I monitored the LED on power-up, as you suggested. I also tried
completely removing and reseating some ICs, and swapping some identical
ones between sockets, but still no success. I did however get the LED
to do something slightly different...
I now remember what you describe about the LED from playing with a
working A1000 in the past -- it starts out at half-brightness, then
flashes, and switches to full brightness after a few seconds. On mine,
the LED had been lighting at full brightness, immediately at power-up.
Never a dim stage. (I am sure of this, because I was later able to
make it power up at half-bright and compare the two. Read on...)
So, it lit up at full-brightness immediately on power-up. I left the
unit on for about 10 mins, but not many ICs ever got warm. The three
in the lower-left of the mainboard, at locations U4A, U4C, U4E felt
like they got up to normal operating temperature. The 68000 felt only
5 to 10 degrees warmer than room temp, and it's 72 F in here -- it felt
pretty dead. No other ICs seemed to heat at all. This seems like a
pretty low-level problem.
I tried swapping the two EPROMs ("Kick ROMs") between their sockets,
and no change. After confirming that they're both the same chip, I
then tried swapping the two 8520s between their sockets too. A-ha,
something changed! When powering up, I no longer got just a
full-brightness LED. It would come on dim, then immediately flash
bright 5 times in rapid succession, and return to dim. I guess this is
the diagnostic firmware reporting a problem? If it had been bright
after the flash, it would mean the test passed, right? Foolishly, I
did not look at the video screen to find an error code -- I didn't have
video connected at the time. :(
So, why will the machine not yield any response when the 8520s are in
their default positions, but it gives a diagnostic error when they are
swapped? Is one of them dead? Maybe. Or it could be the sockets. So
I proceeded to check the sockets... First I swapped the 8520s back to
their original positions, just to make sure, and again got a steady
full-brightness LED, as I first did. I swapped them yet again back to
their swapped positions, and again got the flashing LED returning to
dim. Maybe it is one of the 8520s that is dead!
However, I continued to try checking sockets... Those 3 ICs which were
actually heating -- at U4A, U4C, and U4E -- I pulled them out
completely and reseated them. Change again! The LED will no longer
flash -- it just stays dim, and does nothing else. I swapped the 8520s
yet again back to default positions -- again a full-brightness LED
that's never dim. Swapped them back to their "swapped" positions, and
again a dim LED that doesn't flash! Arrrgh! Now I can't get it to
even flash again!
So then, I pulled ALL socketed ICs out, bent all their pins slightly
inward, by gently pressing their pin edges against a hard plastic
surface, to better contact the socket's connectors. Then I reseated
them all in their sockets. Still the same -- dim LED that doesn't
flash. I am perplexed! But I'm still not giving up...
I'm now, after I send this message, going to whip out my meter again
and check for continuity in all the pins of all the sockets, between
the soldered connections on the mainboard and the pins on the ICs.
There really aren't that many when you consider how many pins are on a
typical processor nowadays, and the DIP package layout makes it easy.
If I find any opens, I'm at the point where I just want to pull ALL of
those sockets out, and solder the ICs directly on the mainboard! Well,
maybe I'll leave the Kick ROMs socketed.
I remember seeing some time ago that a friend of mine had an Amiga
diagnostic doodad (of course, she didn't know what it was though,
heehee). It consisted of connectors (don't ask me which ones) and a
box with LEDs on it, intended for diagnosing hardware problems that the
Amiga itself couldn't. I would have borrowed it, but it wasn't for the
Amiga 1000 -- it was for 500 and 2000, maybe some other models too.
But I remembered thinking why people would need these doodads, unless
they were technicians who deal with Amigas heavily. But now I
understand, LOL! It's a shame that such a revolutionary computer had
to have such hardware problems. It's also a shame that it wasn't
recognized by more of the public than it was. If you ask me, it was a
technological marvel and still is. Why has there been such a lack of
public acceptance of the Amiga platform in the industry??
Also, I must admit that these IC sockets look pretty cheap. Why would
cheap sockets be put into a computer which was supposed to
revolutionize the industry? I think it's always a good idea to socket
ICs so they can be replaced easily if need be, but if you're not using
good sockets, it's better to leave them out entirely. There are
machine-pinned sockets available easily, that "hug" the IC pins, and
make a much better connection. Would this really have upset the
development budget that much?
Enough of my rambling... I'll talk to you later! Hope to hear from you
soon!
I'll leave our existing thread...
In article <QR3v6.28$j07....@nsw.nnrp.telstra.net>, "Clockmeister"
<gerr...@tnet.com.au> wrote:
--
I'm only human. Corrections to any technical info I give are welcome.
<<Please remove the word "SPLAT" from either below address to use it.>>
Email: mailto:Toast...@SPLATbigfoot.com
ToasterKing
Okay, about the staying-dim-and-not-flashing thing, I'm a retard.
Before I removed and reseated those three ICs at U4A, U4C, and U4E, I
removed the daughterboard so I could gain access to them, and forgot to
put the daughterboard back before testing in subsequent attempts. Doh!
I can be so thickheaded sometimes... I don't know why that
daughterboard seems so foreign to me.
Anyway, I'm now getting the startup tune, and a white screen!!! The
startup sequence, as exhibited on my machine at this time, is as
follows:
Power-on --> LED blinks 5 times then remains dim --> ~10 second delay
--> startup chime --> white screen
However, the little "Insert Kickstart disk" icon never appears on the
white screen, and it never tries to access the floppy, even when
there's a disk in it. It makes no difference whether the internal
floppy drive is connected or not -- I still get no icon.
Also, something else here seems weird -- connecting the keyboard seems
to lock up the whole computer, from what I can tell... If the keyboard
is connected to the RJ-11 keyboard connector in the back when the
system is powered on, it won't even do a diagnostic check (i.e. LED
does not flash) and it's stuck at a black screen forever.
Disconnecting the keyboard while the system is on results in a hard
reset, though this might be normal -- I don't know. I probably am not
supposed to try it anyway. Ctrl-Amiga-Amiga does not work on the
keyboard.
I've also found that the system will still boot this far when one of
the 8520s is removed, the one at U6N. If the one if U6P is removed
instead, I don't even get the flashing LED. Could this 8520 be fried?
At least now we know that the power supply, clock oscillator, CPU, and
probably Kick ROMs are okay, right? I'm kinda leaning toward that 8520
as a suspect, just from my testing trials... check this out...
I'll call one of the 6520s "chip 1" and the other "chip 2" -- these
don't refer to either in particular as packaged in the factory board
configuration. "Chip 1" is the one I think is good, and "Chip 2" is
the one I think may be fried. These are both identical 8520s,
according to the part numbers on them.
Inserted in...
Socket U6P | Socket U6N | Result
============================================================
Chip 1 Chip 2 Boots to white screen
Chip 2 Chip 1 No flashing LED, no response
Chip 1 [none] Boots to white screen
Chip 2 [none] No flashing LED, no response
[none] Chip 1 No flashing LED, no response
[none] Chip 2 No flashing LED, no response
So, the system will ONLY boot as far as it does IF AND ONLY IF "Chip 1"
-- the one I think is good -- is in socket U6P. No other variables
here seem to matter.
The way I interpret this is:
a) Chip 2 is bad, because it won't boot the computer in socket U6P as
Chip 1 does, and also
b) a chip must be in socket U6P to start the boot process, but the one
in U6N isn't needed until later (when the system would normally show me
the insert kickstart disk icon)
These are just educated guesses, but they're all I have to go on. I
can't seem to find much of anything on the Web about Amiga 1000!
The description for the 8520 on IC Master is listed as "Video RAM
Controller/Driver (up to 256K bits)". This would make sense to me that
it is in fact this chip -- if video RAM cannot be allocated when
expected at startup, then the computer in effect cannot start up!!!
Correct? I am guessing that each controls a different bank of Video
RAM, and the one that is used first at power-on is the one controlled
by the 6520 at U6P. Is this right?
IC Master also says that this IC was made by National Semiconductor,
and has now been discontinued. No replacement is available from NTE
Electronics. Yay. This should be fun to find.
--
I'm only human. Corrections to any technical info I give are welcome.
<<Please remove the word "SPLAT" from either below address to use it.>>
Email: mailto:Toast...@SPLATbigfoot.com
Patrick Ford
> At least now we know that the power supply, clock oscillator, CPU, and
> probably Kick ROMs are okay, right? I'm kinda leaning toward that 8520
> as a suspect, just from my testing trials... check this out...
>
> I'll call one of the 6520s "chip 1" and the other "chip 2" -- these
> don't refer to either in particular as packaged in the factory board
> configuration. "Chip 1" is the one I think is good, and "Chip 2" is
> the one I think may be fried. These are both identical 8520s,
> according to the part numbers on them.
>
> Inserted in...
> Socket U6P | Socket U6N | Result
> ============================================================
> Chip 1 Chip 2 Boots to white screen
> Chip 2 Chip 1 No flashing LED, no response
> Chip 1 [none] Boots to white screen
> Chip 2 [none] No flashing LED, no response
> [none] Chip 1 No flashing LED, no response
> [none] Chip 2 No flashing LED, no response
I would say you have identified the problem. If both were good, swapping
them would make no difference.
>
> So, the system will ONLY boot as far as it does IF AND ONLY IF "Chip 1"
> -- the one I think is good -- is in socket U6P. No other variables
> here seem to matter.
>
> The way I interpret this is:
> a) Chip 2 is bad, because it won't boot the computer in socket U6P as
> Chip 1 does, and also
> b) a chip must be in socket U6P to start the boot process, but the one
> in U6N isn't needed until later (when the system would normally show me
> the insert kickstart disk icon)
>
> These are just educated guesses, but they're all I have to go on. I
> can't seem to find much of anything on the Web about Amiga 1000!
>
> The description for the 8520 on IC Master is listed as "Video RAM
> Controller/Driver (up to 256K bits)".
It does more than that. It's involved in both serial and parallel ports,
Floppy drive, one or both mouse buttons.
> This would make sense to me that
> it is in fact this chip -- if video RAM cannot be allocated when
> expected at startup, then the computer in effect cannot start up!!!
> Correct? I am guessing that each controls a different bank of Video
> RAM, and the one that is used first at power-on is the one controlled
> by the 6520 at U6P. Is this right?
>
> IC Master also says that this IC was made by National Semiconductor,
> and has now been discontinued. No replacement is available from NTE
> Electronics. Yay. This should be fun to find.
A500s are so cheap now they are almost free. Software Hut has 8520s.
--
--
My domain contains .co, not .com as appears in the header.
+=+=+=+=+=+=+=+=+=+=+=+=+=+=+==+=+=+=+=+=+=+=+=+=+=+=+=+=+
Patrick Ford Auckland, Aotearoa (New Zealand)
Harvesters, send spam directly to:
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Clockmeister
ToasterKing wrote in message
<270320010734317485%Toast...@SPLATmindless.com>...
>Finally, some signs of life!!
>
>Okay, about the staying-dim-and-not-flashing thing, I'm a retard.
>Before I removed and reseated those three ICs at U4A, U4C, and U4E, I
>removed the daughterboard so I could gain access to them, and forgot to
>put the daughterboard back before testing in subsequent attempts. Doh!
>I can be so thickheaded sometimes... I don't know why that
>daughterboard seems so foreign to me.
It was deleted in later A1000's ;-) I have one of each with my hacked one
(the pics on my webpage) being the same as yours in that is has a
daughterboard also.
>Anyway, I'm now getting the startup tune, and a white screen!!! The
>startup sequence, as exhibited on my machine at this time, is as
>follows:
>
>Power-on --> LED blinks 5 times then remains dim --> ~10 second delay
>--> startup chime --> white screen
>
>However, the little "Insert Kickstart disk" icon never appears on the
>white screen, and it never tries to access the floppy, even when
>there's a disk in it. It makes no difference whether the internal
>floppy drive is connected or not -- I still get no icon.
OK,
>Also, something else here seems weird -- connecting the keyboard seems
>to lock up the whole computer, from what I can tell... If the keyboard
>is connected to the RJ-11 keyboard connector in the back when the
>system is powered on, it won't even do a diagnostic check (i.e. LED
>does not flash) and it's stuck at a black screen forever.
>Disconnecting the keyboard while the system is on results in a hard
>reset, though this might be normal -- I don't know. I probably am not
>supposed to try it anyway. Ctrl-Amiga-Amiga does not work on the
>keyboard.
Does the caps-lock light blink? I hazard to guess not.
>I've also found that the system will still boot this far when one of
>the 8520s is removed, the one at U6N. If the one if U6P is removed
>instead, I don't even get the flashing LED. Could this 8520 be fried?
Yes.
>At least now we know that the power supply, clock oscillator, CPU, and
>probably Kick ROMs are okay, right? I'm kinda leaning toward that 8520
>as a suspect, just from my testing trials... check this out...
>
>I'll call one of the 6520s "chip 1" and the other "chip 2" -- these
>don't refer to either in particular as packaged in the factory board
>configuration. "Chip 1" is the one I think is good, and "Chip 2" is
>the one I think may be fried. These are both identical 8520s,
>according to the part numbers on them.
>
> Inserted in...
>Socket U6P | Socket U6N | Result
>============================================================
>Chip 1 Chip 2 Boots to white screen
>Chip 2 Chip 1 No flashing LED, no response
>Chip 1 [none] Boots to white screen
>Chip 2 [none] No flashing LED, no response
>[none] Chip 1 No flashing LED, no response
>[none] Chip 2 No flashing LED, no response
>
>So, the system will ONLY boot as far as it does IF AND ONLY IF "Chip 1"
>-- the one I think is good -- is in socket U6P. No other variables
>here seem to matter.
Indeed, this seems to be a CIA problem with one of your chips.
>The way I interpret this is:
>a) Chip 2 is bad, because it won't boot the computer in socket U6P as
>Chip 1 does, and also
>b) a chip must be in socket U6P to start the boot process, but the one
>in U6N isn't needed until later (when the system would normally show me
>the insert kickstart disk icon)
CIA's handle Input/Output, and guess what the floppy drive is ;-)
>These are just educated guesses, but they're all I have to go on. I
>can't seem to find much of anything on the Web about Amiga 1000!
There isn't much is there. I'm still chasing schematics... anyone?
>The description for the 8520 on IC Master is listed as "Video RAM
>Controller/Driver (up to 256K bits)". This would make sense to me that
>it is in fact this chip -- if video RAM cannot be allocated when
>expected at startup, then the computer in effect cannot start up!!!
>Correct? I am guessing that each controls a different bank of Video
>RAM, and the one that is used first at power-on is the one controlled
>by the 6520 at U6P. Is this right?
>
Nope, they are IO chips as I mentioned above. If you can't initialize the
floppy drive, as the one of the CIA's contol some floppy functions, the
A1000 will hang at the white screen. The keyboard is also an input, which
explains why that isn't working also.
>IC Master also says that this IC was made by National Semiconductor,
>and has now been discontinued. No replacement is available from NTE
>Electronics. Yay. This should be fun to find.
>
Where do you live?
Do you have a Commodore 64 with socketed CIA (6520 from memory) chips?
Regards,
Clockmeister.
phineas
Thus wrote gerr...@tnet.com.au in "comp.sys.amiga.hardware":
>
[snip]
> I'm still chasing schematics... anyone?
If you mean the ones in the A1000 manual - provided my memory doesn't play
tricks on me - I might be able to dig that out and scan it.
C'ya,
--
Paul. Presently on:
A4000D '030/25, 2+16MB, OS3.9, IDE: 1 + 1GB, Picasso IV + MV1438,
Concierto, MF III + 56k, Epson C StylusII
Clockmeister
phineas wrote in message <3AC265E3.M...@NOSPAM.demon.co.uk>...
>
>Thus wrote gerr...@tnet.com.au in "comp.sys.amiga.hardware":
>>
>[snip]
>> I'm still chasing schematics... anyone?
>
>If you mean the ones in the A1000 manual - provided my memory doesn't play
>tricks on me - I might be able to dig that out and scan it.
>
>
Well, yeah... if the A1000 schematics are in the manual. (A500 and A2000
schematics are).
I'd love you like a brother if you scanned them for me ;-)
Regards,
Clockmeister.
phineas
Thus wrote gerr...@tnet.com.au in "comp.sys.amiga.hardware":
>
> phineas wrote in message <3AC265E3.M...@NOSPAM.demon.co.uk>...
> >
> >Thus wrote gerr...@tnet.com.au in "comp.sys.amiga.hardware":
> >>
> >[snip]
> >> I'm still chasing schematics... anyone?
> >
> >If you mean the ones in the A1000 manual - provided my memory doesn't play
> >tricks on me - I might be able to dig that out and scan it.
> >
> >
>
> Well, yeah... if the A1000 schematics are in the manual. (A500 and A2000
> schematics are).
That was a bit silly of me to rush in without checking first, but I
could have sworn they were in there. I just unboxed the old A1k to
check - sadly only the port connectors are in the manual...
> I'd love you like a brother if you scanned them for me ;-)
Ah well, sorry, it wasn't to be.
LordPistachio
>them would make no difference.
Thank you Patrick! I felt reasonably confident in my diagnosis, but
your words make it all the more comforting. =)
An 8520 lists as $9.95 a piece at Software Hut, which is not exactly a
wholesale price, but not that high either -- besides, I'm never gonna
find it anywhere else! I think I will go that route. Thank you for
the recommendation on a source!! =) *big pat on the back* :-)
>It does more than that. It's involved in both serial and parallel ports,
>Floppy drive, one or both mouse buttons.
Those IC descriptions are always very brief, like a one-liner at most.
Had I known all it was responsible for all this, I may have even found
it earlier. Thank you!!
>A500s are so cheap now they are almost free. Software Hut has 8520s.
I might consider it a waste to buy a used A500 just to gut it for the
A1000, when that system could potentially go to someone else who really
wants it. I would rather have an IC that hasn't been used in a machine
for many years already anyway, and wouldn't want to destroy a whole
machine to get another working, when I don't have to. But thank you!!
I found the 8520 at Software Hut and think I'm going to purchase the
1-piece there. Again, thank you very much!!!
ToasterKing
>>daughterboard seems so foreign to me.
>
>It was deleted in later A1000's ;-) I have one of each with my hacked one
>(the pics on my webpage) being the same as yours in that is has a
>daughterboard also.
Yes, I looked at those pics on your webpage. Quite an impressive feat!
I've done some hardware hacks myself (but on systems I was familiar
with, unlike this one, LOL!). Usually I would only try it if I at
least found partial documentation... pinouts at the very least... but
there have been numerous exceptions all the same. :-)
Just out of curiosity, how many motherboard revisions of the A1000 were
there? I have REV 6. The ICs on that daughterboard aren't even very
densely packed, and it looks like those custom "piggyback" connectors
could potentially create a problem. Still, they made it fit, and it
works. So that's good! =)
I hope they fixed some of the hardware problems in later revisions.
From what I've read, it looks like there were a lot (due to poor
circuit design, low-quality integrated circuits, or what?). And could
you educate me on this... which companies have owned the Amiga name or
contributed to its development? I know there were several, one being
Commodore.
>Does the caps-lock light blink? I hazard to guess not.
Caps-Lock doesn't blink on its own, which I'm guessing means the I/O
hardware isn't initializing the keyboard bus? The light will come on
and go off when I press the caps-lock key, but only a limited number of
times, and regardless of boot progress.
>>I've also found that the system will still boot this far when one of
>>the 8520s is removed, the one at U6N. If the one if U6P is removed
>>instead, I don't even get the flashing LED. Could this 8520 be fried?
>
>Yes.
Nice. That was relatively easy.
>Indeed, this seems to be a CIA problem with one of your chips.
Had the machine not had two of those CIA chips, I would have been lost,
because without swapping chips, next to no spare parts, and no
knowledge of the mainboard logic, I would have been lost!! (I guess I
could spend weeks reading up on the docs of all the ICs in the unit,
and then many many hours probing pins for logic, though!)
>CIA's handle Input/Output, and guess what the floppy drive is ;-)
>
>>These are just educated guesses, but they're all I have to go on. I
>>can't seem to find much of anything on the Web about Amiga 1000!
>
>There isn't much is there. I'm still chasing schematics... anyone?
Afraid I can't help you much with those. They're something I also
chase frequently. If the schematics you need are on individual ICs or
other common circuit components, I could refer you to a friend I know
in Canada who can find _anything_ electronic -- he does it for a
living. He may also be able to find Amiga-specific schematics, but I
surely wouldn't promise anything there. He does charge a 10% markup on
any items you decide to purchase from him though. He's been doing
electronics repairs, mods, and circuit design for several decades.
Email me at address below (watch out -- anti-spam protected!) if you
want his contact info.
>Nope, they are IO chips as I mentioned above. If you can't initialize the
>floppy drive, as the one of the CIA's contol some floppy functions, the
>A1000 will hang at the white screen. The keyboard is also an input, which
>explains why that isn't working also.
Bingo! Thank you ever so much!!
>>IC Master also says that this IC was made by National Semiconductor,
>>and has now been discontinued. No replacement is available from NTE
>>Electronics. Yay. This should be fun to find.
>>
>
>Where do you live?
Near Greenville, SC, USA
Most obscure ICs I need to buy, I either find an equivalent replacement
by NTE Electronics which I can get through a local distributor, or I
buy in quantity from the manufacturer or a reseller (but not all
companies will even do this), or I go through my guy in Canada.
>Do you have a Commodore 64 with socketed CIA (6520 from memory) chips?
I do have one Commodore 64, but I'm keeping it -- it's definitely not
getting gutted! I'm not sure about the CIA chips in it as I've never
studied the board that closely. Why do you ask? Is the 6520
interchangeable with the 8520 in this case? (What are differences?)
Thanks so much for all of your help and for educating me!! You've
helped quite a bit, and it was fun learning about the A1000 from you
also! You should have some job in computer hardware architecture... do
you do anything outside of your garage Amiga work? =)
Geoff Oltmans
Clockmeister wrote:
> >If you mean the ones in the A1000 manual - provided my memory doesn't play
> >tricks on me - I might be able to dig that out and scan it.
> >
> >
>
> Well, yeah... if the A1000 schematics are in the manual. (A500 and A2000
> schematics are).
>
> I'd love you like a brother if you scanned them for me ;-)
There weren't any in my manual. I had to buy them separately, and they
are quite large.
*Geoff!*
Clockmeister
ToasterKing wrote in message
<310320010447514555%Toast...@SPLATmindless.com>...
>>>I can be so thickheaded sometimes... I don't know why that
>>>daughterboard seems so foreign to me.
>>
>>It was deleted in later A1000's ;-) I have one of each with my hacked one
>>(the pics on my webpage) being the same as yours in that is has a
>>daughterboard also.
>
>Yes, I looked at those pics on your webpage. Quite an impressive feat!
>I've done some hardware hacks myself (but on systems I was familiar
>with, unlike this one, LOL!). Usually I would only try it if I at
>least found partial documentation... pinouts at the very least... but
>there have been numerous exceptions all the same. :-)
For most of those hacks I had pretty decent documentation thanks to a few
helpfull fellow online hackers. Some schematics needed debugging though.
I also built the homebrew A500 IDE interface (2 of actually) which work
well with an A500 but not the A1000 due to the bus noise, even with the PAL
grounding hack or later revision daughterboard less A1000.
>Just out of curiosity, how many motherboard revisions of the A1000 were
>there? I have REV 6. The ICs on that daughterboard aren't even very
>densely packed, and it looks like those custom "piggyback" connectors
>could potentially create a problem. Still, they made it fit, and it
>works. So that's good! =)
It works, but the A1000 design, particularly the earlier A1000's with the
daughterboard have excessive bus noise. There are hacks to help solve this
problem, but they don't always work.
I couldn't tell you how many revisions of motherboard there are, but I think
there where quite a few.
The earliest A1000's weren't capable of the EHB mode, so if you have one of
these you have one of the first releases.
>I hope they fixed some of the hardware problems in later revisions.
>From what I've read, it looks like there were a lot (due to poor
>circuit design, low-quality integrated circuits, or what?).
Usual story... C= wanted the A1000 released, but it wasn't quite ready but
it was rushed through anyway. (Something to do with the release of the Atari
ST before the Amiga probably)
And could
>you educate me on this... which companies have owned the Amiga name or
>contributed to its development? I know there were several, one being
>Commodore.
Originally Hi-Toro designed the Amiga, but ran out of money. Commodore
bought Amiga out from under Atari's nose from Hi-Toro. When Commodore went
broke in 1994 Amiga was sold to Escom, a German company. Escom continued to
sell Amigas (A1200 and A4000), but didn't spend much on development mainly
because they also went broke.
Gateway 2000 (as it was known as then) then bought the Amiga. After a lot of
bullshit about MMC's and BIG announcements, Gateway decided to pull the pin
on the new Amiga developments before anything much was achieved.
Gateway sold the name, and licensed some of the technology patents (I think)
to Amino (or something like that). At this point I lost interest, mainly
because any developments now have nothing to do with the old Amiga.
<snip>
>>There isn't much is there. I'm still chasing schematics... anyone?
>
>Afraid I can't help you much with those. They're something I also
>chase frequently. If the schematics you need are on individual ICs or
>other common circuit components, I could refer you to a friend I know
>in Canada who can find _anything_ electronic -- he does it for a
>living. He may also be able to find Amiga-specific schematics, but I
>surely wouldn't promise anything there. He does charge a 10% markup on
>any items you decide to purchase from him though. He's been doing
>electronics repairs, mods, and circuit design for several decades.
>Email me at address below (watch out -- anti-spam protected!) if you
>want his contact info.
That's OK, I'm bound to come across the schematics sooner or later. There is
a guy local to me who apparantly has them, so I'll see if he wants to sell
or swap for some gear.
>>Nope, they are IO chips as I mentioned above. If you can't initialize the
>>floppy drive, as the one of the CIA's contol some floppy functions, the
>>A1000 will hang at the white screen. The keyboard is also an input, which
>>explains why that isn't working also.
>
>Bingo! Thank you ever so much!!
>
>>>IC Master also says that this IC was made by National Semiconductor,
>>>and has now been discontinued. No replacement is available from NTE
>>>Electronics. Yay. This should be fun to find.
>>>
>>
>>Where do you live?
>
>Near Greenville, SC, USA
>Most obscure ICs I need to buy, I either find an equivalent replacement
>by NTE Electronics which I can get through a local distributor, or I
>buy in quantity from the manufacturer or a reseller (but not all
>companies will even do this), or I go through my guy in Canada.
Patrick's reply suggested a reasonably good place to purchase considering
where you live. If you had been in Australia, I would have posted one over
to you for free.
>>Do you have a Commodore 64 with socketed CIA (6520 from memory) chips?
>
>I do have one Commodore 64, but I'm keeping it -- it's definitely not
>getting gutted! I'm not sure about the CIA chips in it as I've never
>studied the board that closely. Why do you ask? Is the 6520
>interchangeable with the 8520 in this case? (What are differences?)
Yes, I've heard that one of the 8520's can be interchanged with a 6520. The
A1000 won't work 100%, but basic functionality can be tested this way. (I
believe there may be problems with serial/parallel access and the clock, but
for basic functionality and games these aren't needed)
It is basically the same chip.
>Thanks so much for all of your help and for educating me!! You've
>helped quite a bit, and it was fun learning about the A1000 from you
>also! You should have some job in computer hardware architecture... do
>you do anything outside of your garage Amiga work? =)
>
I'm a predelivery manager for a motor vehicle dealership, was a PC tech and
am an Amiga fan.
Electronics are a hobby ;-)
Regards,
Clockmeister.
Clockmeister
phineas wrote in message <3AC547CE.M...@NOSPAM.demon.co.uk>...
>
>Thus wrote gerr...@tnet.com.au in "comp.sys.amiga.hardware":
>>
>> phineas wrote in message <3AC265E3.M...@NOSPAM.demon.co.uk>...
>> >
>> >Thus wrote gerr...@tnet.com.au in "comp.sys.amiga.hardware":
>> >>
>> >[snip]
>> >> I'm still chasing schematics... anyone?
>> >
>> >If you mean the ones in the A1000 manual - provided my memory doesn't
play
>> >tricks on me - I might be able to dig that out and scan it.
>> >
>> >
>>
>> Well, yeah... if the A1000 schematics are in the manual. (A500 and A2000
>> schematics are).
>
>That was a bit silly of me to rush in without checking first, but I
>could have sworn they were in there. I just unboxed the old A1k to
>check - sadly only the port connectors are in the manual...
>
>
>
>> I'd love you like a brother if you scanned them for me ;-)
>
>Ah well, sorry, it wasn't to be.
>
D'oh!
Never mind, thanks for trying anyway :-)
Regards,
Clockmeister.
Clockmeister
Geoff Oltmans wrote in message <3AC5E88D...@email.uah.edu>...
Didn't the A1000 schematics come a one large single sheet of paper?
Regards,
Clockmeister.
Geoff Oltmans
Clockmeister wrote:
> Didn't the A1000 schematics come a one large single sheet of paper?
Mine is a set of schematics from a third party called Cardinal or
something. There are about 6 sheets, and they are something like
4ftx2ft. They are large. It's also got schematics of the mouse.
I have another almost complete set, except it's missing the page with
all the custom chips on it.
*Geoff!*
ToasterKing
<gerr...@tnet.com.au> wrote:
> I also built the homebrew A500 IDE interface (2 of actually) which work
>well with an A500 but not the A1000 due to the bus noise, even with the PAL
>grounding hack or later revision daughterboard less A1000.
That's quite impressive! I assume you know a thing or two about
digital logic and circuit design, then? (Well of course you do --
probably even had classes in it if you were a PC tech) I'd be
interested in seeing schematics of this or learning a little more about
it, and what kind of ICS you used. Was yours the first gadget to
feature IDE interfacing on the Amiga?
>It works, but the A1000 design, particularly the earlier A1000's with the
>daughterboard have excessive bus noise. There are hacks to help solve this
>problem, but they don't always work.
>I couldn't tell you how many revisions of motherboard there are, but I think
>there where quite a few.
>The earliest A1000's weren't capable of the EHB mode, so if you have one of
>these you have one of the first releases.
Problems with noise for some reason does not surprise me, especially
with that funny daughterboard, where none of the connectors are
shielded. I became a bit suspicious of whether the unit had known
noise/interference problems the first time I opened up the case and saw
that huge piece of aluminum shielding covering the entire innards of
the machine and secured by 14 screws. =)
What does the bus noise affect? What kinds of results does it produce?
I'd expect it would cause data corruption and errors along the bus,
especially in external devices or ones which are not grounded perfectly
(and maybe have some inline chokes or ferrite-donut protectors :-) ).
I'm sure this is known to cause system crashes as well. You mentioned
grounding the PALs -- are these the PALs on the daughterboard? What's
the essence of the hack (gotta be more than just running thicker ground
wires or shields, methinks)? I hope the logic chips on this noisy bus
employ some kind of parity-checking or other error correction! (But my
guess would be they don't.) It might be tough keeping the whole bus in
sync anyway if data constantly has to be retried. Anyway, I'm
rambling...
I don't know what EHB mode is... so how do I know if my board supports
it? =) I have much to learn, heehee.
>>I hope they fixed some of the hardware problems in later revisions.
>>From what I've read, it looks like there were a lot (due to poor
>>circuit design, low-quality integrated circuits, or what?).
>
>Usual story... C= wanted the A1000 released, but it wasn't quite ready but
>it was rushed through anyway. (Something to do with the release of the Atari
>ST before the Amiga probably)
This explains a lot. =) And yes, the story's all too familiar. It
seems though, from the number of help posts I've read about hardware
problems and the variety of the problems, that Amigas had more than
their share. :( I don't remember much from that era, as I was busy
conquering my dreams on my Apple IIgs, =) but it seems to me that the
Atari ST was pretty hot in comparison to the Amiga, though I do know
several people who had A1000's.
>Originally Hi-Toro designed the Amiga, but ran out of money. Commodore
>bought Amiga out from under Atari's nose from Hi-Toro. When Commodore went
>broke in 1994 Amiga was sold to Escom, a German company. Escom continued to
>sell Amigas (A1200 and A4000), but didn't spend much on development mainly
>because they also went broke.
>
>Gateway 2000 (as it was known as then) then bought the Amiga. After a lot of
>bullshit about MMC's and BIG announcements, Gateway decided to pull the pin
>on the new Amiga developments before anything much was achieved.
>
>Gateway sold the name, and licensed some of the technology patents (I think)
>to Amino (or something like that). At this point I lost interest, mainly
>because any developments now have nothing to do with the old Amiga.
I remember now hearing stories about Gateway's affiliation in the
project. I also remember wondering why I suddenly stopped hearing news
about it, like it had never happened. So the platform has been dragged
through a rough and rocky terrain. Maybe you couldn't say that the
technology is still the same, but in some way a tradition has
definitely been carried on. The torch has been passed many times, and
it's been through violent weather, but still I can't help thinking that
for some, the dream still lives on, in the ones who want to keep the
Amiga alive forever. =)
Pardon me, I tend to get rather prosaic when defending old computer
platforms that are now a part of yesterday's song -- it's one of my
passions, LOL. My main flame though is still my Apple IIgs -- I've
upgraded the heck out of it and still use it all the time, and brag
about it -- and its userbase (and that of other Apple II's) still seems
quite a bit larger than the Amiga's, I hate to say. I've also a
Commodore 64 which I love to play old games on, and many old Macs. All
the Macs and the IIgs are networked and internet-ready.
Which reminds me... what options do I have in adding a hard disk to
the Amiga 1000 (assuming I get it working)? I know there are SCSI
controllers still lurking around, which I'd really prefer over the
older IDE standard, and already have many of those drives anyway. What
are the names of some of these, pros/cons, and what additional hardware
might I need (besides cables/cases/power supplies)? And the serial
port -- despite the opposite-gender connector from x86 machines (as
with the parallel port also :-) ), is it RS-232?
Despite not knowing much about the hardware, I have used them many
times, and have long since been a fan.
>That's OK, I'm bound to come across the schematics sooner or later. There is
>a guy local to me who apparantly has them, so I'll see if he wants to sell
>or swap for some gear.
Just let me know if you change your mind. He has or can find schems of
most everything... actually knowing him, Amiga schematics might be a
piece of cake. =)
>Patrick's reply suggested a reasonably good place to purchase considering
>where you live. If you had been in Australia, I would have posted one over
>to you for free.
Thanks to Patrick, I have purchased the 8520's from that very same
site!!! (Actually only purchased 1 piece -- very tight on cash right
now and it wasn't exactly a wholesale price. ;-) )
>Yes, I've heard that one of the 8520's can be interchanged with a 6520. The
>A1000 won't work 100%, but basic functionality can be tested this way. (I
>believe there may be problems with serial/parallel access and the clock, but
>for basic functionality and games these aren't needed)
>
>It is basically the same chip.
Well, I would have already tried this if I'd known, but now the 8520
has already been ordered. Perhaps tomorrow I may open up my old friend
(the C64) and borrow one of his major organs, but one more day and the
8520 will be here anyway. =)
>I'm a predelivery manager for a motor vehicle dealership, was a PC tech and
>am an Amiga fan.
>Electronics are a hobby ;-)
>
>Regards,
>
>Clockmeister.
They've always been a hobby for me too, but am hoping to turn that
hobby into a career once the opportunity arises. It's been really nice
talking with you about a common interest like this one. =)
BTW, you remind me a bit of a chum I had on comp.sys.apple2, always
knowledgeable and helpful, and conversative. Even the name is similar
-- he calls himself Supertimer. =)
Clockmeister
ToasterKing wrote in message
<030420010207307181%Toast...@SPLATmindless.com>...
>In article <Yemx6.9$1v1....@nsw.nnrp.telstra.net>, "Clockmeister"
><gerr...@tnet.com.au> wrote:
>
>> I also built the homebrew A500 IDE interface (2 of actually) which work
>>well with an A500 but not the A1000 due to the bus noise, even with the
PAL
>>grounding hack or later revision daughterboard less A1000.
>
>That's quite impressive! I assume you know a thing or two about
>digital logic and circuit design, then? (Well of course you do --
>probably even had classes in it if you were a PC tech) I'd be
>interested in seeing schematics of this or learning a little more about
>it, and what kind of ICS you used. Was yours the first gadget to
>feature IDE interfacing on the Amiga?
Well, it wasn't really my design - I just built it and made it work. I had
some ideas for my own design, but it was much easier using existing ideas
because I couldn't program a driver to save my life. Never did get much past
TRS-80/C64 BASIC you see ;-)
http://www.students.tut.fi/~leinone3/ide.html
The URL for the design...
>>It works, but the A1000 design, particularly the earlier A1000's with the
>>daughterboard have excessive bus noise. There are hacks to help solve this
>>problem, but they don't always work.
>>I couldn't tell you how many revisions of motherboard there are, but I
think
>>there where quite a few.
>>The earliest A1000's weren't capable of the EHB mode, so if you have one
of
>>these you have one of the first releases.
>
>Problems with noise for some reason does not surprise me, especially
>with that funny daughterboard, where none of the connectors are
>shielded. I became a bit suspicious of whether the unit had known
>noise/interference problems the first time I opened up the case and saw
>that huge piece of aluminum shielding covering the entire innards of
>the machine and secured by 14 screws. =)
Quite right. The later, daughterboard-less A1000's where a bit better.
>What does the bus noise affect? What kinds of results does it produce?
>I'd expect it would cause data corruption and errors along the bus,
>especially in external devices or ones which are not grounded perfectly
>(and maybe have some inline chokes or ferrite-donut protectors :-) ).
Yep. Problems are mainly with external devices, especially if you have more
then one hanging off the expansion bus. For instance, my RAM expansion and
Sidecar can't be used at the same time because the system becomes very
unstable and hangs/Guru's all the time.
>I'm sure this is known to cause system crashes as well. You mentioned
>grounding the PALs -- are these the PALs on the daughterboard? What's
>the essence of the hack (gotta be more than just running thicker ground
>wires or shields, methinks)? I hope the logic chips on this noisy bus
>employ some kind of parity-checking or other error correction! (But my
>guess would be they don't.) It might be tough keeping the whole bus in
>sync anyway if data constantly has to be retried. Anyway, I'm
>rambling...
Yes, the PAL grounding hack is exactly as you described. Unlike A500/A2000
etc the A1000 is missing the Gary chip which is a single custom chip
designed to do what all those PAL chips do on the A1000.
>I don't know what EHB mode is... so how do I know if my board supports
>it? =) I have much to learn, heehee.
It's a graphics mode that allowed the display of 32 (or 64, can't remember)
by halving the brightness of the colours. The earliest A1000's didn't have
that capability (yours should as it's a Rev 6)
>>>I hope they fixed some of the hardware problems in later revisions.
>>>From what I've read, it looks like there were a lot (due to poor
>>>circuit design, low-quality integrated circuits, or what?).
>>
>>Usual story... C= wanted the A1000 released, but it wasn't quite ready but
>>it was rushed through anyway. (Something to do with the release of the
Atari
>>ST before the Amiga probably)
>
>This explains a lot. =) And yes, the story's all too familiar. It
>seems though, from the number of help posts I've read about hardware
>problems and the variety of the problems, that Amigas had more than
>their share. :( I don't remember much from that era, as I was busy
>conquering my dreams on my Apple IIgs, =) but it seems to me that the
>Atari ST was pretty hot in comparison to the Amiga, though I do know
>several people who had A1000's.
I've owned an ST, but it is nowhere near as interesting or capable as an
Amiga 1000. Still a good system though, given the timeframe.
That depends largely on where you live. I don't know anyone around here with
a Apple IIgs, but know quite a few people with ST's or Amigas. There are
certainly more Amiga users then C64 users.
I've also a
>Commodore 64 which I love to play old games on, and many old Macs. All
>the Macs and the IIgs are networked and internet-ready.
>
>Which reminds me... what options do I have in adding a hard disk to
>the Amiga 1000 (assuming I get it working)? I know there are SCSI
>controllers still lurking around, which I'd really prefer over the
>older IDE standard, and already have many of those drives anyway. What
>are the names of some of these, pros/cons, and what additional hardware
>might I need (besides cables/cases/power supplies)? And the serial
>port -- despite the opposite-gender connector from x86 machines (as
>with the parallel port also :-) ), is it RS-232?
The connector link on my site has the specs for the A1000's ports. They are
different to PC/ other Amiga ports, not just in gender.
As far as SCSI HDD boards go, I don't know. Some of the A500 designed ones
work, and I think there are IDE solutions but not many for the 1000.
>Despite not knowing much about the hardware, I have used them many
>times, and have long since been a fan.
>
>>That's OK, I'm bound to come across the schematics sooner or later. There
is
>>a guy local to me who apparantly has them, so I'll see if he wants to sell
>>or swap for some gear.
>
>Just let me know if you change your mind. He has or can find schems of
>most everything... actually knowing him, Amiga schematics might be a
>piece of cake. =)
No probs, thank you, I'll keep that in mind ;-)
>>Patrick's reply suggested a reasonably good place to purchase considering
>>where you live. If you had been in Australia, I would have posted one over
>>to you for free.
>
>Thanks to Patrick, I have purchased the 8520's from that very same
>site!!! (Actually only purchased 1 piece -- very tight on cash right
>now and it wasn't exactly a wholesale price. ;-) )
You should only need one ;-)
>>Yes, I've heard that one of the 8520's can be interchanged with a 6520.
The
>>A1000 won't work 100%, but basic functionality can be tested this way. (I
>>believe there may be problems with serial/parallel access and the clock,
but
>>for basic functionality and games these aren't needed)
>>
>>It is basically the same chip.
>
>Well, I would have already tried this if I'd known, but now the 8520
>has already been ordered. Perhaps tomorrow I may open up my old friend
>(the C64) and borrow one of his major organs, but one more day and the
>8520 will be here anyway. =)
I wouldn't bother since you have the real thing coming. No point putting the
C64's organs at risk is there...
>>I'm a predelivery manager for a motor vehicle dealership, was a PC tech
and
>>am an Amiga fan.
>>Electronics are a hobby ;-)
>>
>>Regards,
>>
>>Clockmeister.
>
>They've always been a hobby for me too, but am hoping to turn that
>hobby into a career once the opportunity arises. It's been really nice
>talking with you about a common interest like this one. =)
Likewise ;-)
>BTW, you remind me a bit of a chum I had on comp.sys.apple2, always
>knowledgeable and helpful, and conversative. Even the name is similar
>-- he calls himself Supertimer. =)
LOL, wasn't me - honest!
Regards,
Clockmeister.
Ville Jouppi
<Toast...@SPLATmindless.com> wrote:
>>Usual story... C= wanted the A1000 released, but it wasn't quite ready but
>>it was rushed through anyway. (Something to do with the release of the Atari
>>ST before the Amiga probably)
>
>This explains a lot. =) And yes, the story's all too familiar. It
>seems though, from the number of help posts I've read about hardware
>problems and the variety of the problems, that Amigas had more than
>their share. :( I don't remember much from that era, as I was busy
>conquering my dreams on my Apple IIgs, =) but it seems to me that the
>Atari ST was pretty hot in comparison to the Amiga, though I do know
>several people who had A1000's.
Hmm, the ST was not hot compared to the Amiga except for the fact that it was
a lot cheaper.. The Amiga's specs bowled over the ST in almost every aspect.
:-)
--
CBM, PEZ, and TI-calc nut, Scout, Glider pilot, Programmer
Email: vjo...@sci.fi, URL: http://www.sci.fi/~vjouppi/
GSM: +358-40-5679999, IRCNet: Jope
"I see", said the blind man as he picked up his hammer and saw.
Clockmeister
Ville Jouppi wrote in message
<488jctga4b71nql41...@4ax.com>...
>On Tue, 03 Apr 2001 02:07:30 -0400, ToasterKing
><Toast...@SPLATmindless.com> wrote:
>
>>>Usual story... C= wanted the A1000 released, but it wasn't quite ready
but
>>>it was rushed through anyway. (Something to do with the release of the
Atari
>>>ST before the Amiga probably)
>>
>>This explains a lot. =) And yes, the story's all too familiar. It
>>seems though, from the number of help posts I've read about hardware
>>problems and the variety of the problems, that Amigas had more than
>>their share. :( I don't remember much from that era, as I was busy
>>conquering my dreams on my Apple IIgs, =) but it seems to me that the
>>Atari ST was pretty hot in comparison to the Amiga, though I do know
>>several people who had A1000's.
>
>Hmm, the ST was not hot compared to the Amiga except for the fact that it
was
>a lot cheaper.. The Amiga's specs bowled over the ST in almost every
aspect.
>:-)
Well, everything except for that standard MIDI port on ST's. Whilst the
Atari crowd will argue that a MIDI port as standard was such a great thing
to have, I would argue that having Paula as the sound chip instead of that
horrible Yamaha chip more then made up for the Amiga not having a MIDI port
as standard.
Just listen to the intro to the Xenon2 (Bomb the Bass - Megablast) tune on
an ST and compare...
The ST version is literally a joke...
Regards,
Clockmeister.
Ville Jouppi
wrote:
>Ville Jouppi wrote in message
>>
>>Hmm, the ST was not hot compared to the Amiga except for the fact that it
>was
>>a lot cheaper.. The Amiga's specs bowled over the ST in almost every
>aspect.
>>:-)
>
>Well, everything except for that standard MIDI port on ST's. Whilst the
>Atari crowd will argue that a MIDI port as standard was such a great thing
>to have, I would argue that having Paula as the sound chip instead of that
>horrible Yamaha chip more then made up for the Amiga not having a MIDI port
>as standard.
Yeah, the MIDI-port I had in mind when I said almost every aspect. :-)
>Just listen to the intro to the Xenon2 (Bomb the Bass - Megablast) tune on
>an ST and compare...
>The ST version is literally a joke...
Too true. The Mega STs(??) were ok, IIRC .. I remember we listened to
starglider on an Amiga and an ST and they sounded alike..
Stalky T Fish
>In article <Yemx6.9$1v1....@nsw.nnrp.telstra.net>, "Clockmeister"
><gerr...@tnet.com.au> wrote:
>
>I don't know what EHB mode is... so how do I know if my board supports
>it? =) I have much to learn, heehee.
EHB=Extra Half Bright mode. Gives you 64 colors in 320x200/400
modes by using the 6th color bit to signal the intensity of the
corresponding color from the 32 color palette. Off the top of
my head (and it's been a while) The Denise chips that did EHB
were labeled "8362R8". The originals were "8362R5" and the ECS
ones are "8362R11". All of the R8's I've ever seen had plastic
cases, not gold/ceramic. R8's and R11's are drop-in replacements
for R5's, though.
>Which reminds me... what options do I have in adding a hard disk to
>the Amiga 1000 (assuming I get it working)? I know there are SCSI
>controllers still lurking around, which I'd really prefer over the
>older IDE standard, and already have many of those drives anyway. What
>are the names of some of these, pros/cons, and what additional hardware
>might I need (besides cables/cases/power supplies)? And the serial
>port -- despite the opposite-gender connector from x86 machines (as
>with the parallel port also :-) ), is it RS-232?
That male-gender parallel connector is probably the reason your 1000
had a blown 8520. (I wish I had read your original post when it
was first posted. I was like, "ooh! ooh! blown 8520! blown 8520!")
Blown 8520s are a very common problem with Amigas and can lead to
all sorts of wierd behavior from a dead machine to barely noticeable
timing irregularities. On the 1000, people would often ignore the
warning in the manual and attempt to plug peripherals into the
parallel port with it turned on. The male connector made it very
easy to short the live, unbuffered pins to ground. Other times,
people would mistake it for a serial port and their modem would
happily send +/- 12V into a port designed for only 0/+5V.
>>Yes, I've heard that one of the 8520's can be interchanged with a 6520. The
>>A1000 won't work 100%, but basic functionality can be tested this way. (I
>>believe there may be problems with serial/parallel access and the clock, but
>>for basic functionality and games these aren't needed)
>>
>>It is basically the same chip.
>
>Well, I would have already tried this if I'd known, but now the 8520
>has already been ordered. Perhaps tomorrow I may open up my old friend
>(the C64) and borrow one of his major organs, but one more day and the
>8520 will be here anyway. =)
Not a 6520, a 6526. It's soldered in on some C64's though. There is a
slight difference in the clock architectures of the 8520 and 6526, so
it's not an exact match, but if you have a dead machine, it'll get you
up to a CLI at least. I used one on my 1000 while waiting for an 8520
to arrive.
...Sean.