Help with a Model 100/102 Floppy Drive Question... Please :-)
David Grissom
I recently acquired a Brother FB100 floppy disk drive (more or less
equivalent to a TPDD-1).
No cable.. of course :-)
Being resourceful and deadly with a soldering iron I decided to make one
using the plans found on the Club 100 site (TPDD.DO from Marty Goodman -
1989). Followed the recipe carefully but my limited knowledge of
electronics has grown rusty.
[snipped from document]
TPDD
8 pin Dual In Line DB 25 RS232
connector wires connector signal direction
------------------- ---------- ----------------
gnd 1 ------------------------------------- 7 gnd
CTS 2 ------------------------------------- 4 RTS to TPDD
DTR 3 --------o--->l----------------------- 6 DSR from TPDD
l
22K resistor
l
gnd
RTS 4 ---------o--->l----------------------- 5 CTS from TPDD
l
22K resistor
l
gnd
DSR 5 ------------------------------------- 20 DTR to TPDD
*TXD 6 ---------o--->l----------------------- 3 RD from TPDD
l
22K resistor
l
gnd
*RXD 7 -------------------------------------- 2 TD to TPDD
8 not connected 1, 8-19, 21-25 all
(inclusive) not connected
Alas, I cannot get it to work :-(
I have a TS-DOS chip in my model 100 (Supposed to be the best!).
I removed the solder bridge from the Brother Drive (no dip switches in this
little drive - I will add a bank later). However, I tried it with and
without the bridge. Drive appears to come on (small click when a disk is
inserted and the power is on. A momentary blink of the low battery light
when the power is turned off. Hey, the disk reject works great! In a
nutshell, I have little to no information about the FB100.
Any suggestions? Anyone still with this list ever successfully built one of
these cables? I am going to try to reverse the diodes but hope that some
skilled individual will enlighten me on this project.
As a last resort, anyone have an extra cable they would let me rent to see
if the drive is OK (It looks unused - that could mean it never worked). I
am on a tight budget with my wife controlling the purse strings. She says
food is more important that computers (Boy, does she live in a dream world.)
:-)
I really would like to see these 2 old devices talk...
David Grissom
David Grissom
Rick
And what does TS-DOS report when you start the program? IIRC it
should report an error message if it can't find a drive.
> I removed the solder bridge from the Brother Drive (no dip switches in this
> little drive - I will add a bank later). However, I tried it with and
> without the bridge. Drive appears to come on (small click when a disk is
> inserted and the power is on. A momentary blink of the low battery light
> when the power is turned off. Hey, the disk reject works great! In a
> nutshell, I have little to no information about the FB100.
I'm not sure what you mean by a "solder bridge" on this unit but
don't kill the drive. There is no dipswitch because none is needed.
It only operates at one transfer rate - 9600 baud. You may want to
check if there are any settings in TS-DOS that need to be set
accordingly. It won't work if the software is set for a 19,200 baud
transfer rate.
> Any suggestions? Anyone still with this list ever successfully built one of
> these cables? I am going to try to reverse the diodes but hope that some
> skilled individual will enlighten me on this project.
Do you have the original power supply?
If not are you sure you are using one with sufficient current and
with the correct polarity? The Tandy PDD wouldn't work all that
reliably unless you were using fresh batteries or a power supply
rated at 6v with 400 mA *minimum* current output. The cheap, generic
300 mA power supplies aren't sufficient and can cause the drive to
prematurely shut down. And if the polarity of the supply output is
wrong that could be lethal... This is all presumptive info based on
the Tandy drives. I have no idea what the OEM supply for the Brother
drive is rated at.
If you're not sure how to orient the diodes and aren't confident
about your soldering skills you might be best off to ask around for
someone to create a cable for you.
David Grissom
My answers to your questions and comments:
1. TS-DOS does not appear to have any baud adjustments (at least I haven't
found any.) As soon as I select the Drive menu while in TS-DOS, I get an
immediate "Drive not Ready".
2. I had removed a solder bridge (original OEM setup) and replaced it to see
if that would work.
3. I have put the diodes in both ways. No response. Actually, I am pretty
good at soldering and checking my work. There were no tested shorts or open
circuits. The diodes seemed to work fine.
4. I don't have an original power supply. The unit uses a 6V adapter or 4
AA batteries. (Note: This unit looks identical to the Tandy drives(TPDD1).
Physically the only difference is that it does not have dip switches.). I
used fresh NMH batteries. I tried the drive with a 6 volt 700mA adapter.
5. When I switch the drive on I hear a slight click inside the drive (heads
repositioning). When I switch it off the low battery light flickers for a
fraction of a second.
7. I tried using some advice from Ron on the M100 mailing list. I used
Telecom set at 9600 and some specific commands. I could not get a response
from the drive.
The drive may be bad. However, It may be that I am using the wrong
components. I originally went to the Shack and picked up the components
that seem to match the requirements. However, the diodes may not be
equivalent.
Anyway, unless I can acquire a test cable or arrange for someone to test the
drive with a known good cable, I am just about ready move on to other
hopeless projects. (I am trying to get a disk drive to work in a Tandy 1100
FD. I need a new belt (the old one literally dissolved due to age.).
Thanks
"Rick" <rick...@rcn.com> wrote in message news:40D913BC...@rcn.com...
> David Grissom wrote:
> >
> > Hi,
> >
> > I recently acquired a Brother FB100 floppy disk drive (more or less
> > equivalent to a TPDD-1).
> >
> > No cable.. of course :-)
> >
> > Being resourceful and deadly with a soldering iron I decided to make one
> > using the plans found on the Club 100 site (TPDD.DO from Marty Goodman -
> > 1989). Followed the recipe carefully but my limited knowledge of
> > electronics has grown rusty.
> >
> > [snipped from document]
> >
> > TPDD
> > 8 pin Dual In Line DB 25 RS232
> > connector wires connector signal
direction
>
------------------- ---------- ----------------
> > gnd 1 ------------------------------------- 7 gnd
> I'm not sure what you mean by a "solder bridge" on this unit but
> don't kill the drive. There is no dipswitch because none is needed.
> It only operates at one transfer rate - 9600 baud. You may want to
> check if there are any settings in TS-DOS that need to be set
> accordingly. It won't work if the software is set for a 19,200 baud
> transfer rate.
>
>
Rick
>
> Thanks Rick for your response.
>
> My answers to your questions and comments:
> 1. TS-DOS does not appear to have any baud adjustments (at least I haven't
> found any.) As soon as I select the Drive menu while in TS-DOS, I get an
> immediate "Drive not Ready".
It may still be the cable. According to the TS-DOS manual: "Your
disk drive is not turned on, or it is not connected to your
computer."
I looked at the instructions for making the cable at:
http://www.club100.org/library/ups/bruce_birkner/tpdd.do
and the one thing not clearly covered is the physical pin layout for
the drive connector side of things. There are logical possiblities,
like:
1234
5678
1234
8765
1357
2468
And since this connector is so non standard, and the instructions
for making the cable don't specify what the placement is for pin 1
etc... ?
The Tandy manual/schematic for a PDD2 doesn't help either. The
schematic just lists the drive connections in a straight line as
such:
8 EB+
6 TXD
4 RTS
3 DTR
1 OV
7 RXD
5 DSR
2 CTS
I don't have access to a PDD and cable right now. (Buried somewhere
in the closet.) Anyone know the pin orientation on the PDD
connector?
Rick
David Grissom
1357
2468
I believe that I set up one of the other combinations - however, I can't
remember which one.
Incidently, I used 1N914 (1N4148) Silicon Switching Diodes RS 276-1122 and
the Resisters were 1/4 watt RS 271-1339
Thanks again, for taking time to respond. I believe it is probably the
cable. There was an after market cable on sale recently at eBay. I am
going to try to reach him to check for another cable or how he built it.
David Grissom
"Rick" <rick...@rcn.com> wrote in message news:40DE2BAB...@rcn.com...
F.J. Kraan
> I tried the
>
> 1357
> 2468
+----+
+--+ +--+
|1 3 5 7|
|2 4 6 8|
+----------+
Looking into the cable end, this is correct. I measured these shorts:
8 pin 25p sub-D
1 7 GND
2 4 CTS
3 6 DTR
6 3 TXD
This convinced me. Let me know if you want more data. My cable is the
original that came with the TDD2.
>>
>>8 EB+
>>6 TXD
>>4 RTS
>>3 DTR
>>1 OV
>>7 RXD
>>5 DSR
>>2 CTS
Fred Jan Kraan
David Grissom
I finally got my Brother FB-100 to work with my Model 100. My homemade
cable just could not cut the mustard. :-(
I was able to buy a cable from Lou Palmer (Lou sells these cables and other
neat M100 stuff on eBay). This cable is well built and works very well!. I
want to thank Lou for his help and suggestions.
This drive has no jumpers (except a solder bridge on Position 1 - closest to
the back of the drive). To get the drive to recognize what was going on, I
used staples (yes - common Swinglines :-) ). I jumpered all connections in
lew of the switches. Lo and behold the little drive came to life. From
there it was all downhill. My TS-DOS functions perfectly. Everything is
great. Note: Tandys disk software for the TPDD1 will not work because of
the 9600 Baud transfer rate of the Brother.
The nice thing about this drive is that it is virtually brand new! The belt
is in great shape. No dust or other problems.
This is really cool!
Thanks
D. Grissom
"David Grissom" <#dgri...@knology.net> wrote in message
news:10ds4lc...@corp.supernews.com...