OS65D Almost Boots Then Fails

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lowrybt1
Posts: 116
Joined: Sun Mar 08, 2015 3:42 pm

OS65D Almost Boots Then Fails

Post by lowrybt1 » Thu Jul 13, 2017 2:54 am

I’ve rebuilt a real, live os65d 3.3 diskette (5.25) and am working to duplicate a bunch of them to offer on this forum. Made many revisions to Frank Knepp’s single disk copy program to get to this point. Also worked around a buggy track zero copy utility in 3.3. Just tried copying a diskette. On boot up, everything sounds perfect but I end up with a blank screen. (I know diagnosing based on head tracking sounds is very amateurish). I went over the copier program with a fine-tooth comb, made sure the calls and saves are referencing the right memory locations, tracks, sectors, pages. Also looked track by track at the sector/page formatting which is all good.

This brings back mildly bad memories of this happening when I worked with my C1PMF 36-37 years ago.

I’ll try copying to another diskette (obvious next step) but I’m wondering if there might be some quick diagnostic steps I could follow through a warm reset and the Monitor. Any thoughts?

Tom
C4PDF w. 24K, 2 x 5.25 MPI B-51 drives
C1P RevB with fully-populated 610 board and A-13. Klyball D-13.
Spares: 600 Rev.D, 610 board, 540A, A-13 with homebuilt data separator, MPI B-51 logic board (w/o data sep module) and mechanicals

dave
Site Admin
Posts: 485
Joined: Tue Sep 09, 2008 5:24 am

Re: OS65D Almost Boots Then Fails

Post by dave » Thu Jul 13, 2017 5:05 pm

following with interest. How did you rebuild the disk?

Dave

lowrybt1
Posts: 116
Joined: Sun Mar 08, 2015 3:42 pm

Re: OS65D Almost Boots Then Fails

Post by lowrybt1 » Fri Jul 14, 2017 2:10 am

I need to credit Grant with a huge, major assist. More than a year ago, he provided lod files track by track for v3.3. I finally succeeded this week in reading the files through the ACIA on a C1PMF using a TTL-USB serial adapter. Then saved them one by one to disk following steps Grant had provided. Put together a disk with tracks 0-15. Found Frank Knepp's single drive copier in an issue of the Aardvark Journal which was written for V3.2. I used the memory map and track/sector/page info in the V3.3 manual to revise the program to appropriately CA and SA tracks/sectors/pages in the v3.3 OS. This provide to a frustrating step in the process because I put full faith in the track/sector/page data in the V3.3 manual. Of course it turned out to be wrong regarding tracks 6 and 11. Figured that out by using the DI XX command on my one, newly built disk. Now I have the copier updated correctly and have tried using it to copy new disks. But those won't boot all the way.

One issue I've had to negotiate: the track zero read/write utility on my new disk freezes during the Read (Rnnnn) operation. I got around that by using the track zero copier from a V3.2 disk to copy track zero from my newly built disk to the copies I'm trying to make.

I cannot figure out what is going wrong with the copying process. Will scrutinize the copier code again tomorrow. Maybe I entered something incorrectly and keep missing it.
C4PDF w. 24K, 2 x 5.25 MPI B-51 drives
C1P RevB with fully-populated 610 board and A-13. Klyball D-13.
Spares: 600 Rev.D, 610 board, 540A, A-13 with homebuilt data separator, MPI B-51 logic board (w/o data sep module) and mechanicals

MK14HAK
Posts: 296
Joined: Wed Mar 16, 2011 1:49 am
Location: New Zealand

Re: OS65D Almost Boots Then Fails

Post by MK14HAK » Fri Jul 14, 2017 10:36 pm

Try this Tom.
Attachments
TK0RW_C4 _300.zip
(1.21 KiB) Downloaded 36 times
600RevB:16K,2MHz,64x32,470,CEGMON
SuperKit:502,540B,542B,CEGMON, 8" and 5" FDDs
Cards:PE IO,6522 D-A-D, AY3-8910,ProgramGraphics,Color,UK101
WIP:Archive/Restore Util,HexDOS,FDD Emulator

lowrybt1
Posts: 116
Joined: Sun Mar 08, 2015 3:42 pm

Re: OS65D Almost Boots Then Fails

Post by lowrybt1 » Mon Jul 17, 2017 2:32 am

Solved. I did have a mismatch in memory locations between a track CA and SA in the single disk copy program I wrote. Now able to produce V3.3 5.25 diskettes for C2/4/8
C4PDF w. 24K, 2 x 5.25 MPI B-51 drives
C1P RevB with fully-populated 610 board and A-13. Klyball D-13.
Spares: 600 Rev.D, 610 board, 540A, A-13 with homebuilt data separator, MPI B-51 logic board (w/o data sep module) and mechanicals

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