Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
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Re: Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
OK great, USB working. All modules were programmed with Chucky's Diagrom (A500) after test. Try programming the appropriate diagrom for your machine. Try both byte swaps if unsure. You can find out which ROM slot is selected over USB from the info command.
Re: 27C400 EPROM emulators (beta) issue D technical discussion
Solid 5.04v, measured on the accelerator card.Maximilian wrote: ↑Mon Jan 03, 2022 4:06 am I wouldn't directly suspect the caps on the motherboard but if there are a few things wrong...
What is the 5V at the CPU?
Re: Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
Alas still issue with purple screen on power on (in my rev 6.2 A2000). But was able to program the KS3.2.1 *.bin file (for physical chips, not the swapped *.rom ones for emulators), so the ST micro is fine.
As you say you ship with diagrom, but that purple screened as well. Real physical 27C400 KS3.1 works fine.
Will do some reading on A2000 purple screens, but it looks like no code is running from the ROM, not floppy clicks, nothing.
Re: Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
Tried burning both rom/bin files with and without byte swap, no joy.
Reseated socket several times.
LED does not light up, but not sure under which conditions it should ?
Versions are; is an update available ?
STM32 firmware 0.8 (C)2020 Chris Morley
CPLD firmware 0.10 (C)2020 Chris Morley
Nothing conclusive on purple boot, its not an official colour.
Reseated socket several times.
LED does not light up, but not sure under which conditions it should ?
Versions are; is an update available ?
STM32 firmware 0.8 (C)2020 Chris Morley
CPLD firmware 0.10 (C)2020 Chris Morley
Nothing conclusive on purple boot, its not an official colour.
Re: Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
Sorry, I don't know what LED you are talking about.
If you send it back I can test it.
If you send it back I can test it.
Re: Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
Hi,
The "enable LED" option on the EPROM emulator,.. sorry i thought it might have been an indication LED.
Will play a bit more, p.s now i can program images its pretty cool to use, just like the JTAG devices we use at work.
The "enable LED" option on the EPROM emulator,.. sorry i thought it might have been an indication LED.
Will play a bit more, p.s now i can program images its pretty cool to use, just like the JTAG devices we use at work.
Re: Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
oh. you can connect an LED to one of the pads. e.g. to power LED on a C64. I don't think anyone uses this function - especially not on Amiga.
If you have been adjusting options rerun the setup wizard for 27C400 which will reset all the defaults for pull ups etc.
Re: Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
I have now tested two versions of HC533 firmware, with no improvement.
Both work fine with a ROM chip but crash as before with the emulator in place.
Re: Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
Sorry without seeing your Amiga motherboard on a bench with test equipment I can't really help. My guess would be that you have a problem with noise or ground bounce on your board and the EPROM emu responds (and crashes the bus) where a real EPROM can't respond in time. You could try a different Gary (which creates /ROMEN signal IIRC) if you have a spare.
Re: Amiga not booting ( was 27C400 EPROM emulators (beta) issue D technical discussion)
Yeah, no worries. It's a puzzler. I'll maybe try to get a signal trace off /ROMEN and see what it looks like.