I am having some issues with a GVP T-Rex (Rev 4.S) and an A3000 Desktop. The A3000 has 16MB ZIP memory installed and the GVP T-Rex has 8MB of GVP SIMM memory (2 x 4MB) installed. The A3000 roms are OS3.1 (40.68) and I'm running OS3.9.
Are there any known problems with the GVP T-Rex accessing the on-board memory of the A3000? I've narrowed down the problem to motherboard memory access faults with the T-Rex by using MemCheck. I get lots of address errors when MemCheck tests the motherboard memory but none with the GVP SIMM memory (the memory pattern read/write test seem to pass, but the address check fails). Now, I've tried my older A3640 card instead of the T-Rex and there are no errors using MemCheck with the motherboard memory. The T-Rex seems to have no problems with the rest of the system including ECS chipset, SCSI etc...
I've tried booting from both HDD and floppy while trying caches on/off, setpatch on/off etc... and the T-Rex still fails with the motherboard memory.
So, tested A3000 scenarios are:-
GVP T-Rex + 8MB GVP SIMMs + 16MB motherboard ZIP = boot ok (until all GVP memory is allocated, then errors)
GVP T-Rex + 8MB GVP SIMMs + 0MB motherboard ZIP = boot ok
GVP T-Rex + 0MB GVP SIMMs + 16MB motherboard ZIP = doesn't boot or guru
C= A3640 + 16MB motherboard ZIP = boot ok
The A3000 has motherboard rev 8.9, DMAC rev 4, Ramsey rev 7 and Buster rev 11. The ROM and ZIP memory jumpers are set to 25MHz. The ZIP memory is Fast Page and the speed is 80ns. I originally had 8MB of static column memory installed, but it produced the same problem.
A3000 board jumpers are:-
BRDCLOCK: 2-3 (INT) (T-Rex doesn't boot with EXT)
CPUCLOCK: 1-2 (INT)
QUADCLOCK: 1-2 (25MHz)
FPU: 1-2 (OFF)
GVP T-Rex jumpers are:-
JP1: - RESERVED... no jumper fitted
JP2: - RESERVED... no jumper fitted
JP3: - RESERVED... no jumper fitted
JP4: - STARTUP MODE... ON = Motherboard CPU present (ie A3000)
JP5: - RESERVED... no jumper fitted
JP6: - 4040 BOARD ENABLE... no jumper fitted
JP7: - BURST MODE... ON = Enabled.
JP8: - RESERVED... no jumper fitted
JR1: - BURST WRITES... ON (jumper fitted)
JR2: - BURST READS... ON (jumper fitted)
JR3: - SIMM SIZE... OFF = 4MB SIMMs.
JR4: - RESERVED... no jumper fitted
JR5: - RESERVED... no jumper fitted
JR6: - RESERVED... Pins 2 & 3 connected.
There seems to be an amazing lack of information regarding correct jumper settings for this board.
Any help would be appreciated.
Regards,
Stephen.
