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bazzle592
July 17th, 2017, 04:42 PM
I recently picked up an IBM 5170 with a 5153 monitor. I was able to get the monitor working pretty well by replacing a couple capacitors, at which point I thought I was home free. I was wrong.

The machine had a dead battery, so all CMOS settings were lost. I tried to load the setup floppy to no avail (the floppy drive kept making seek test sounds and not loading the floppy; eventually dumping me into BASIC). I know that these older IBM drives sometimes need lots of cleaning before they fully work, so next, I swapped drive A out for the nicest, most reliable, Japanese made 5.25" floppy drive that I own. I started to boot the machine again, but this time instead of making seek test sounds when it came time to boot something, it just started to force the drive heads as far forward as it possibly could, causing the drive to make some horrible gear-grinding sounds. Needless to say, the boot was not successful. It did the same with another drive I tried out.

Is there some jumper setting that i'm missing on the drive? I know for a fact that the Setup disk I have is good (I was able to boot a non-IBM machine off of it), and I know the floppy drive itself is good. When the machine did an actual seek test before trying to load a floppy, it seemed to be communicating with the drive just fine. Any suggestions on where to go from here?

modem7
July 17th, 2017, 11:59 PM
Note that for now, you can perform SETUP via BASIC. Details at [here (http://minuszerodegrees.net/5170/setup/5170_setup.htm)].

Regarding the floppy drive:
* Verify that the cable is the one shown at [here (http://minuszerodegrees.net/images3/floppy_crossover_cable_wiring.jpg)].
* Is termination being done per [here (http://minuszerodegrees.net/diskette/5.25_floppy_drive_termination.jpg)] ?
* If it is a 360K drive, ensure that pin 34 is disconnected. (Requirement of 5170.)
* If it is a 1.2M drive, ensure that pin 34 is configured to generate a 'disk changed' signal. (Requirement of 5170.)

RuudB
July 18th, 2017, 05:46 AM
Note that for now, you can perform SETUP via BASIC. Details at [here (http://minuszerodegrees.net/5170/setup/5170_setup.htm)].
Very interesting!

OK, it is logical for most of us but "most" isn't everyone: what about running the program first before performing step 8.2?

bazzle592
July 18th, 2017, 08:48 AM
Thanks for the info! I was able to figure some stuff out.
I couldn't get the floppies working, so I went ahead and did the manual BASIC code. I was still getting configuration errors, the floppies drives still wanted to kill themselves, and nothing was booting.

The machine that I got came with a 1.44MB external drive with controller card (a 6181682), which was wired inside as Drive D. I removed the drive connection from the card which caused even more weird problems, which made me suspicious of the card, so I took it out, and the floppy drives started to load stuff just fine. I was able to load the setup disk without a problem.

The Hard Drive will need a low-level format; there's a lot of corruption on it.

Is there a logical way that I can troubleshoot the problematic controller card (without removing every capacitor from the board one at a time)? I suspect a shorted tantalum capacitor (there's tons of them on the card), but there's no obvious one. It has a couple of those 3-legged capacitors on there as well.

modem7
July 18th, 2017, 11:35 PM
OK, it is logical for most of us but "most" isn't everyone: what about running the program first before performing step 8.2?
The program is indeed run before step 8.2; it is run at step 7.

modem7
July 18th, 2017, 11:52 PM
Is there a logical way that I can troubleshoot the problematic controller card (without removing every capacitor from the board one at a time)? I suspect a shorted tantalum capacitor (there's tons of them on the card), but there's no obvious one. It has a couple of those 3-legged capacitors on there as well.
The "6181682" [photo (http://minuszerodegrees.net/5150_5160/cards/5150_5160_cards.htm#floppy_adapter)] is the floppy controller found in the 5170's predecessors, the IBM 5150 and IBM 5160. It is limited to double density drives only. If it is simply added to the 5170, without doing anything else, then it will conflict with the existing floppy controller circuitry built into the 5170's Fixed Disk and Diskette Drive Adapter [photo (http://minuszerodegrees.net/5170/cards/5170_cards.htm#fddda_1)].

The fact that you, "took it out, and the floppy drives started to load stuff just fine." indicates to me that such a conflict existed.


I suspect a shorted tantalum capacitor (there's tons of them on the card), but there's no obvious one.
A shorted capacitor will overload the power supply, stopping it from starting (although the power supply fan may in some cases still turn).

RuudB
July 19th, 2017, 12:43 AM
The program is indeed run before step 8.2; it is run at step 7.
IMHO step 7 generates the code that has to be typed in at step 8.1.

8.1 [5170] Being very careful, type in the BASIC code that was produced in step 7, noting that lines starting with "REM" can be omitted (they are remarks/comments).
8.2 [5170] Power off the 5170.

I'm still missing the "RUN" part :)

modem7
July 19th, 2017, 11:06 PM
I'm still missing the "RUN" part :)
I see. You mean the BASIC program produced by GSETUP_BASIC, not the GSETUP_BASIC program itself.

GSETUP_BASIC produces BASIC code that has no line numbers. Therefore, no "RUN" is required.

RuudB
July 21st, 2017, 05:12 AM
GSETUP_BASIC produces BASIC code that has no line numbers. Therefore, no "RUN" is required.
Ah, I understand. Thank you for this information!

bazzle592
July 22nd, 2017, 06:38 AM
I am currently trying to write some PC-DOS disks to install onto the hard drive. I will report back if I am able to get the floppy controller configured and working.