Amiga CD32 and DiagROM - What am I doing wrong?

[leonk]

I got a dead CD32 I'm trying to fix. So far I did the following:

- replaced all capacitors
- burned DiagROM 1.2.1 to a M27C800
- connected to my computer via USB to TTL adapter - noticed junk
- Replaced Paula with a known good one - I now see DiagROM booting on serial port (2 pins on AUX plug) but with memory errors
- Replaced the 4 RAM chips with NOS RAM

Now, DiagROM goes through the full boot cycle (output captured below) but there's a few things I noticed:

- When I press any key in Putty, it resets
- Only way to get into diag menu is holding mouse button but then I can't choose anything on the screen using PC keyboard (pressing a key again causes reboot of CD32)
- DiagROM only detects 256kb of RAM - I know RAM is good
- I only see DiagROM output on terminal - video output just has a bunch of colors flashing but never shows the actual output from DiagROM

Thoughts?

Amiga DiagROM V1.2.1 - 16-Jul-20 - By John (Chucky/The Gang) Hertell


Testing if serial loopbackadapter is installed: <> NOT DETECTED
- Parallel Code $ff - Start of ROM, CPU Seems somewhat alive
Checking status of mousebuttons for different startups:

Set all Interrupt enablebits (INTENA $dff09a) to Disabled: Done
Set all Interrupt requestbits (INTREQ $dff09c) to Disabled: Done
Set all DMA enablebits (DMACON $dff096) to Disabled: Done

Testing if OVL is working: OK
- Parallel Code $fe - Test UDS/LDS line
- Test of writing word $FFFF to $400 OK
- Test of writing word $00FF to $400 OK
- Test of writing word $FF00 to $400 OK
- Test of writing word $0000 to $400 OK
- Test of writing byte (even) $ff to $400 OK
- Test of writing byte (odd) $ff to $401 OK
- Parallel Code $fd - Start of chipmemdetection

Addr $00040400 OK Number of 32K blocks found: $08
Chipmem Shadowram detected, guess there is no more chipmem, stopping here

Startaddr: $00000400 Endaddr: $0003FFFF
- Fastmemcheck skipped as we found chipmem
- Parallel Code $fb - Memorydetection done

Using $0002CCEA as start of workmem (Base)

- Parallel Code $fa - Starting to use detected memory

Testing if serial loopbackadapter is installed: <> NOT DETECTED
Detecting if we have a working raster: DETECTED
Detected Chipmem: 256kB
Detected Motherboard Fastmem: 0kB
Basememory address: $0002CCEA
As a very fast test of variablearea working this SHOULD read OK: OK!
- Parallel Code $f9 - Detected memory in use, we now have a stack etc
- Doing Initstuff
- Setting up Chipmemdata
- Copy Menu Copperlist from ROM to Chipmem
- Copy ECS TestCopperlist from ROM to Chipmem
- Copy ECS testCopperlist2 from ROM to Chipmem
- Fixing Bitplane Pointers etc in Menu Copperlist
- Copy Audio Data from ROM to Chipmem
- Do final Bitplanedata in Menu Copperlist
- Initstuff done!

Set Start of copper (COP1LCH $dff080): Done
Starting Copper (COPJMP1 $dff088): Done
Set all DMA enablebits (DMACON $dff096) to Enabled: Done
Set Beam Conter control register to 32 (PAL) (BEAMCON0 $dff1dc): Done
Set POTGO to all OUTPUT ($FF00) (POTGO $dff034): Done
- Parallel Code $f8 - Starting up screen, text echoed to serialport
Amiga DiagROM V1.2.1 - 16-Jul-20 - By John (Chucky/The Gang) Hertell



Doing ROM Checksumtest: (64K blocks, Green OK, Red Failed)
$5A39AC3E $C5724DFE $7C779F2B $00000000 $00000000 $00000000 $00000000 $006C0070

CPU: 68EC20 FPU: NONE MMU: NOT CHECKED

Checking for fastmem
Pressing left mousebutton will cancel detection (if hanged)

Checking if a 24 Bit address cpu is used: YES
- Checking for Memory in 24 Bit area (NON AUTOCONFIG)
- Checking for Memory in Ranger or Fakefast area


IF This ROM is sold, if above 10eur+hardware cost 25% MUST be donated to
an LEGITIMATE charity of some kind, like curing cancer for example...
If you paid more than 10Eur + Hardware + Shipping, please ask what charity you
have supported!!! This software is fully open source and free to use.
Go to www.diagrom.com or http://github.com/ChuckyGang/DiagROM for information



To use serial communication please hold down ANY key now
OR click the RIGHT mousebutton.
Holding down the LEFT mousebutton will force serial on and turn off screen
forcing stuff to run in fastmem if avaible

[leonk]

UPDATE: System fixed. U35 (74F373) was bad. Once replaced, all 2MB chip ram was visible, and everything started working. Another CD32 saved.

[supaduper]

Originally Posted by leonk

UPDATE: System fixed. U35 (74F373) was bad. Once replaced, all 2MB chip ram was visible, and everything started working. Another CD32 saved.

Great work fella