Help with Compupro 68K

[new_castle_j]

Thanks to member hmb for all the help so far! I'm still struggling to get a CompuPro 68K machine working and would like any opinions on what to do next. Here's the details.
CompuPro 68K CPU Rev H1
CompuPro RAM 22 256K
CompuPro Disk 1A Floppy ROM version 291D
CompuPro System Support 1 (with "ECO 179" fix and modification to the IC at U28 as described in manual)
Terminal connected to the System Support 1

I have meticulously verified the jumper and switch settings on all cards, I am attempting to boot from 8" floppy disk of CP/M-68K from CompuPro version 1.3
Terminal is set to DTR/DSR handshake, 19.2K baud 2 stop bits per CompuPro manual.
Powering on the machine and hitting reset will cause the floppy drive A to click, click, click, click, like the head is loading track 0 over and over again, but I never see any output on the console.

I think that some code is being read from the disk because I can see the signals change on the serial cable with my RS232 auto-cabler:
Just powering on my terminal only, (S100 is off) I can verify that DTR (20) is asserted
Next I power on the S100 chassis and DSR (6) from the CompuPro goes low
Next I power on the floppy drive, the head loads and the signals change DSR and CTS from the Compupro go high

Then the floppy just goes click click click, loads the head over and over, never seeking to a track.

How should I go about triage on this?

Thank You!

 

[new_castle_j]

Does anyone out there have a working CompuPro system (doesn't have to be a 68K CPU) with a Disk 1a, and System Support board. Perhaps someone willing to test my boards in their working system to try and determine which of my boards is not working?

 

[retrogear]

I purchased an SS-1 recently and had to change the phantom setting to allow phantom to disable memory for use with DISK1 or DISK1A. That means on the SS-1
set SW1 pin 7 (PHD) ON and pin 8 (PHE) OFF. I think this differs from the default settings in the SS-1 manual.

Larry G

 

[new_castle_j]

Thank You for the suggestion, I checked my settings and SW1-7 I have ON and 8 I have OFF. The CPM-68K manual has documented this.

 

[new_castle_j]

Oops, I put the Disk1A into an extender board to check voltages and accidentally inserted it backwards, 3 capacitors turned into fireworks.

 

[hmb]

Oops, I put the Disk1A into an extender board to check voltages and accidentally inserted it backwards, 3 capacitors turned into fireworks.

Have to admit I have also done that before. The damage may extend beyond just 3 capacitors - with an S100 board inserted backwards you would have reversed the polarity of the boards 5V and ground connections, and +/-16V would have been applied to the board's "power on clear" and "2MHz clock" signal inputs.

 

[new_castle_j]

I replaced the exploded capacitors and with a logic IC tester found 2x 74ls244 and 1x 74lsls373 got fried. The latest voltage check (with board inserted correctly) suggests that at least 1 of the 7804 regulators is not working. That's what I have to replace next.

 

[new_castle_j]

A blessing in disguise!?!?!?

I replaced all 3 7804 regulators and Viola! She boots! Total Paydirt!
Thank You hmb!!

 

[new_castle_j]

The Bios and ROM mods are complete and the CompuPro 68K is cold booting from the S100computers.com CF/IDE board! Claude Sonnet AI did all of the coding, I have a boot loader in ROM that can boot from either CF/IDE or floppy, I can access Damian Wilde's monitor rom after booting, I have a PUTBOOT utility specifically for the IDE board, all code assembles on the CompuPro with AS68 from Digital Research.

https://drive.google.com/file/d/1zXMAYn4YM_LrRxK4wW_zVNVsx07-r2Gy/view?usp=drive_link

 

[smj]

Glad to hear of one of these running again.