• Please review our updated Terms and Rules here

TPDD2 Troubleshooting

G

geekdad

Member
Joined
Sep 20, 2022
Messages
21
I recently got my M102 and TPDD2 out of storage and got the backup battery replaced and a new belt on the TPPDD2 as the original had stretched out over time.

Unfortunately it looks like I have another problem with the TPDD2. It's not reading or writing. When I try to boot process (the com:98 etc) the drive seeks for a few seconds then stops.

I tested the M102 and it's working fine, the serial port is fully functional.

However, when I tested the TPDD2 with TPDDClient the head either isn't reading, writing or both. If I try to read the disk image, the drive reads all the tracks and sectors and creates a file but it's all nulls. If I try to write a disk image it goes through the process without error. But reading the created disk reveals a file filled with nulls again. It won't format either, it fails to verify.

I double checked the cable connection internally including the small ribbon cable and the read/write head cable. everything looks correct. I even tested the connectivity on the read/write cable to back sure the connector was ok between the cbale in the board.

I'm not sure where to look. I don't have a service manual for the TPDD2.
 
Disk is spinning and the head is moving. I can see it move, then pull back, then move again when I try the boot sequence from the M102. It's definitely trying.

The LED on the front of the drive shows activity.
 
Maybe there is a break in the wires that connect to one or both of the heads?
I had a TPDD2 which had damaged heads that eventually fell off.

Have you got a known good disk?
 
TPDDClient is a tool that allows a Windows PC to access files, read and write disk images and format diskettes on a TPDD1 or 2. You'll find it out in the files section of Club100.

I have a couple of known good diskettes. One is the original Tandy TPDD Utility disk and a copy. I've tried other diskettes as well.

I may try running a continuity test on the head cable If it shows open that could be the issue. The TPDD is single sided. The cable has four leads though and without the service manual or schematic, I can't be sure which leads are the actual head.
 
Uh, then why is there just one head on the bottom and a pad on the top?

The TPDD2 is single sided. The bank system has nothing to do with number of sides...
 
Last edited:
perhaps try another client
PDD,EXE is one

PDD 2.10 User Manual

museo.freaknet.org


One quick way could be to run it in DOSBOX with the speed of emulation nice and slow. worth a try to confirm it isnt an issue with TPDDclient

my notes on running PDD.EXE in DOSBOX in Windows 10
* you need to edit the dosbox conf file. found for me in C:\Users\home\AppData\Local\DOSBox
* created a folder C:\DOSBOX
* in here, place PDD.EXE
* once DOSBOX is running, jump into A: and run PDD.
* use a null modem cable to connect to the TPDD1 or TPDD2
* one more thing - I enabled 16550 buffers on the COM1 port in Win10.

edits to dosbox conf:

[cpu]
core=auto
cputype=386_slow
cycles=fixed 100
cycleup=10
cycledown=20


[serial]
serial1=directserial realport:COM1
serial2=disabled
serial3=disabled
serial4=disabled

[autoexec]
mount a c:\DOSBOX
 

Attachments

  • PDD210.ZIP
    26 KB · Views: 2
Last edited:
I can give these a try. I do have slower PC /XT and AT class machines I can run it on.
 
You must log in or register to reply here.
Back
Top