Terrible Fire Accelerators

[mattymuc]

1) no, you don't have to modify jed files
2) voltage regulator is ok, but there're only some pins necessary to program the cpld. You don't have a bad short to ground if there's no smoke but there could be a cold solder point or a short between address or data lines. Check the cpld and ram pins again.
3) did you set the clock buffer jumper correct?
4) you don't need the 68882

Chuckies Diagrom would be a perfect start to see what's going on.

[CRP]

Thanks for the replies.
I will double check the cpld pins but I am seeing no smoke for now...
I did put a jumper on the two leftmost pins of JP1.

About the jed files, I just noticed that the ones on github are possibly outdated, where do I get the most recent ones for a rev 3 board?

thanks

[CRP]

Originally Posted by Chucky

and have a look on the LED! does it change brightness.. (this is something I use as a mantra. as everyone seems to skip this IMPORTANT part of amiga troubleshooting)

no it remains always at same level, exactly as when I turn on the A500 without a cpu

[mattymuc]

Originally Posted by CRP

About the jed files, I just noticed that the ones on github are possibly outdated, where do I get the most recent ones for a rev 3 board?

Use the ones in the dev branch, RC2, 2018-01-15.

[CRP]

Thanks, I just programmed the board with RC2 jeds. Now the screen still remains black, but both leds turn on, and the green one becomes brighter. Before only the green would turn on and never change brightness level.

Also, the wiki says to use -p 1 for the bus jed and -p 0 for the ram jed. Is this correct? I thought bus is the first cpld in the chain.

If the programming is correct then I am afraid I will have to tackle the solder points...

[mattymuc]

So, CPU seems to work.
Please check your solder points on cpld and RAM.

[8 Bit Dreams]

BUS is first in chain, RAM is the second one
are You trying to boot with CF card or from floppy? It takes a while till it start to boot from floppy disk
if green LED shines brighter - it means CPU was initialised

[kgc210]

Another Zorro Card tested (limited testing) and does not conflict with the TF530.
I can't perform much testing due to not having the video slot adapter, but does not impact performance or conflict with RAM / IDE. Will try and do some more in depth testing when I can some how.

GVP Impact Vision 24

As you can see in the screen shot it's playing nice with the GVP Impact A2000-HC+8 Series II and the TF530.

[kgc210]

Or how about an X-Surf-100, RapidRoad, GVP Impact A2000-HC+8 Series II, GVP Impact Vision 24 and for good measures Matze GBA-PII++

[CRP]

Originally Posted by 8 Bit Dreams

BUS is first in chain, RAM is the second one
are You trying to boot with CF card or from floppy? It takes a while till it start to boot from floppy disk
if green LED shines brighter - it means CPU was initialised

When I turn the A500 on, the first time the green led stays dim. If I turn it off and on again, it becomes brighter and the other led turns on and stays lit. The screen always remains black.

I have now checked all solder points of the bus cpld, by verifying continuity between each pin and wherever the trace goes to according to schematics. So the area including cpu, voltage regulator, bus cpld, oscillator should be fine.

Can a black screen be due to issues with ram cpld and chip soldering? I will check those next but too tired for today
Should I program the bus cpld only and clear the other one?

[dalek]

Are you using an eprom or real mask rom for kickstart? If eprom, you might need pullup resistors added to your rev 6a motherboard.

[plasmab]

Grab DiagROM. Trying to diagnose without it is impossible

[CRP]

I am using the original kickstart rom.

I already ordered the 27c400 eproms for diagrom, but I guess it will take some time until they arrive (from China, as usual
So I was looking at some other "menial debugging tasks" to try in the meantime...

[CRP]

Originally Posted by plasmab

Grab DiagROM. Trying to diagnose without it is impossible

While we're here, I would like to thank you for this project. I have zero knowledge of electronics, just did some basic through hole soldering in the past. Thanks to this project I found the excuse to buy some equipment, have learned SMD soldering, and in general started experimenting with other stuff I did know nothing about until now. So Stephen, thanks for the voyage you embarked me on

[plasmab]

Originally Posted by CRP

I am using the original kickstart rom.

I already ordered the 27c400 eproms for diagrom, but I guess it will take some time until they arrive (from China, as usual
So I was looking at some other "menial debugging tasks" to try in the meantime...

Erase the second cpld in the chain and try. This will tell you if the issue is the ram or not.


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[CRP]

I erased the ram cpld, but the screen remains black. Weird, as I believe to have thoroughly checked bus cpld, cpu and accessories solder points.
This is the led behaviour:
1st power on: green turns on but remains dim, yellow remains off
successive power-ons: green turns on, then yellow turns on and remains on, then green becomes brighter
I also get no floppy drive stutters at all.

A kind user has offered to send me a diagrom, so I guess I will wait for that for further dests.

Thanks all!

[plasmab]

Originally Posted by CRP

I erased the ram cpld, but the screen remains black. Weird, as I believe to have thoroughly checked bus cpld, cpu and accessories solder points.
This is the led behaviour:
1st power on: green turns on but remains dim, yellow remains off
successive power-ons: green turns on, then yellow turns on and remains on, then green becomes brighter
I also get no floppy drive stutters at all.

A kind user has offered to send me a diagrom, so I guess I will wait for that for further dests.

Thanks all!

I would look at the solder joints on the resistor networks and especially look at the clock buffers


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[Robban]

Hello!

CRP, did you manage to flash the CPLDs in the wrong order at first? I did exactly that (since it said so in the wiki), and ended up with the same situation for two different TF530s. The CPLDs + 3.3V regulator got very hot for a while until i realized my mistake. Interestingly i could still reach them via JTAG when i had removed the processor and FPU, so i reflashed them in the proper order. Then both cards ended up just showing a black screen (they are sharing one 68030 though, so it might just be that one that burned). Not even Diagrom shows anything on screen.

That is where i left it for now. I'm planning to go at it with oscilloscope when i get the time. I did look at the datasheet for the CPLDs, but could not find any mention of short-circuit protection, so i'm suspecting they got too toasty to work anymore. All part of the TerribleFire experience i suppose

[CRP]

That is one of the things I mentioned in a previous post. I use a Raspi to program the CPLDs, and I followed the wiki instructions, using parameter -p 0 for the RAM cpld, and -p 1 for the bus.
Do you think a CPLD can be burned due to wrong programming?

BTW I have two 68030, but get the same behaviour with both. As a "funny" aside, I found out too late that the 60EC030 does not have the additional pins on the underside that make wrong insertion impossible. Luckily I realized quickly that the CPU was in the socket rotated by 90 degree, and it was getting very hot. I quickly turned off everything and not sure now about the state of that CPU, although the two CPUs still show same behaviour (black screen but life from leds).

[plasmab]

It’s unlikely that any damage would occur with the wrong Jed file in the cpld


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