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Old 26 February 2021, 01:01   #241
Ledfoot
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Quote:
Originally Posted by mkstr View Post
I forgot about halt triggering the menu, but the memtest did pass before that happened indicating that the SRAM is being programmed properly. It kind of looks like a timing issue with this particular machine (between the SRAM and the motherboard), but it seems to work in the vast majority of machines so I'm not sure what could be different here.

How does the diagrom image behave?

Mike

Seemed to work fine, although it does sometimes report RAM errors, but the RAM tests in AmigaTestKit always come back clean.

I just got my KS 1.3/3.1 switcher rom today. Popped it in, both 1.3 and 3.1 booted right up perfectly and ran just fine. It's gotta be something funky between the Romulator and the board, but if the board is working fine with physical chips, I have a hard time pointing to it being the culprit in the equation...
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Old 24 April 2021, 11:40   #242
RoC
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Smile

Like Honey Badger, I am also having issues in getting the A600 romulator working. The Amiga seems to switch-on but the screen is black. The OSSC links the video signal, so something is coming out of it

Both romulator leds are on. I followed the pictures for the orientation (the head towards the trapdooor) and plugged/unplugged a few times. Putting back the orginal 2.05 rom works just fine. The motherboard is without any other expansion, to facilitate the troubleshooting.

I tried to solder the cable both on pin 2 of R511D and pin 3 of Q511. The Q511 is returning a solid caps green on the keyboard, so I assume there is something wrong with that soldering point.
The R511D looks good on the ketboard (no Caps), however the miggy is responding to reset but no screen either.

Tried to format on Windows the 8gigs SD in FAT32, FAT16 on a 4 GB partition but no luck. I understand this should not be the issue, because it should say SD error if something would be wrong with the micro SD.

Beside checking the Romulator with Putty that I am going to do, could I test anything else?

In the worst-case scenario, shall the A600 version be re-utilised for the A500? (I know the form factor is different)

Like Honey Badger, the problem might well be my A600 rev 1.5. It looks good on ATK and never have had problems with that, however it is not recapped and you never know.

Last edited by RoC; 24 April 2021 at 11:48.
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Old 24 April 2021, 12:37   #243
Hercules
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If you ever sell this product through Amiga suppliers, then please do not use Amiga On The Lake (AOTL) for distribution (as with your replacement A1200 keyboards). AOTL's customer service, communication and waiting time were appaling.
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Old 25 April 2021, 21:20   #244
cdh
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The Romulator's STM32 loads ROM code in the SRAM part while holding the Amiga in reset. It's pretty important that the CPU is not on the bus at this point because the STM32 needs to drive the address and data lines on the bus to load code into the SRAM.

Definitely connecting the serial UART will give you a hint as to whether the STM32 CPU is running or not. You can also test access to the SRAM from the UART. As far as I know, there's no easy way to tell that the Romulator is connected to the Amiga bus, but you can at least tell that the SRAM is working and there are no address or data line shorted / floating pins.

If you suspect that the problem is the connection of the reset signal to the Romulator or that the Romulator is not properly driving reset, there might be a simple way to test this. What I've noticed is that even without the reset line connected, if do Ctrl-Amiga-Amiga several times in quick succession right at cold power-on, this will hold the CPU long enough that the Romulator has a chance to load the initial selection program. Then when your CPU begins executing, it will run that selection program. You might have to try this a few times.
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Old 25 April 2021, 23:43   #245
RoC
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Thanks cdh for the advise.

I will test them on the A600, especially the cold-reset trick.

I have an A500 rev 8, can I test it there (paying attention not to short) or the firmware are different?
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Old 25 April 2021, 23:56   #246
cdh
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I'm pretty sure that you can test it in your A500, though you might not have room to put the keyboard in place. I've got an A600 Romulator that I tested in my A2000. Just be aware that the A500/A2000 Romulator has exactly the opposite orientation of the A600 Romulator (the side which has the STM32 sticks out on the other end of the ROM socket). I had to stack a couple 40 pin sockets to raise the Romulator above a board capacitor in my case, but from photos I've seen of the A500 motherboard, it doesn't look like there's anything tall in that area. Just be sure you have pin 1 orientation correct.
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Old 26 April 2021, 23:09   #247
RoC
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The good news is that reset followed by (many) reset actually works. I can get the select screen.

The bad news is that is not lasting long nor it can boot the roms. From what you hinted, it might not hold the reset.

Tried also on a disassembled A500 (just to exclude cold soldering) and the result is the same.
It starts (can hear the Amiga tunes) but then it hangs.

Well looks like my romulator is somehow defective or I have two muggies with issues.

Have more miggies, so I will try on some other system, because sending it back to US is the last measure (if they would be willing to check it)

Thanks for your help
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