I need your help for my Falcon030
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Re: I need your help for my Falcon030
Okay, I'm still checking the problem. when I remove the ram card, the values obtained at cpu init are the same: ssp =$0E2040 and PC=$217900000. So I've removed the rom chip and the processor does not gotten anything ... The chip select is correctly made by Combel... So my problem is "maybe" the rom chip ... I need a new
Re: I need your help for my Falcon030
Could the problem be with one of the GAL's?
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Re: I need your help for my Falcon030
I've maybe some problems with GAL but, now, values received from the rom are never good even in transitory states. So I think my first problem is the rom chip, but it might not be the last...
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Re: I need your help for my Falcon030
My order is placed on Exxos Store Now, i have to wait...
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Re: I need your help for my Falcon030
Hi folks,
I changed the Rom: still nothing.
I reprogram all the GALs: still nothing
I check the data and address continuity between CPU and ROM : All ok.
Have you an idea ? I'm lost
I changed the Rom: still nothing.
I reprogram all the GALs: still nothing
I check the data and address continuity between CPU and ROM : All ok.
Have you an idea ? I'm lost
Re: I need your help for my Falcon030
Maybe this will help ? https://www.exxosforum.co.uk/forum/viewt ... &t=80&p206
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Re: I need your help for my Falcon030
Just a couple of things I'm wondering... (sorry if you've already answered these)
* have you owned this Falcon for a while & it used to work? In what circumstance did it stop working
* Is there any board modifications at all? ie; clock patches, nvram, boosters
* have you owned this Falcon for a while & it used to work? In what circumstance did it stop working
* Is there any board modifications at all? ie; clock patches, nvram, boosters
Re: I need your help for my Falcon030
No, no it's not. The expansion bus is actually a very bad place to test the CPU, unfortunately. It's translated and not fully.silversword31 wrote: ↑Fri Jul 10, 2020 7:09 am Hi,
i've another capture on cold start (tigger on vcc). I don't understand how i can have cpu activity without clock... Is the expansion bus directly connected on 68030 ?
Which explains this. You'll only see DTACKs during DMA.silversword31 wrote: ↑Sat Jul 18, 2020 7:01 pm I've done another capture. I don't understand why the first action of cpu is to write $FFFF. Another curious thing is that /DTACK is totally inactive...
capture1.png
Looking at your snapshot of the start-up sequence:
You can see the CPU looks good -- it asks for the correct two longwords (four 16 bit accesses). The reply to the first two accesses should be 00E0, 0030. This will result in E00030 being the next access. It's not, it's 780000. That's wrong.
So it looks like you're not getting the results from ROM.
That could be caused by COMBEL not decoding the ROM address, but it is issuing a DSACK1 and in another post you see a bus error, so I'd be inclined to think COMBEL is decoding ok.
It could be COMBEL isn't asserting /XROM2, but you've tested that.
It could be the ROM? You've replaced that, but what about its socket? Is the chip getting power, perhaps?
It could be the data lines? Continuity's not enough. We can check it better: remove the ROM chip again. You should be getting FFFF on the data line from the pull-ups. That startup sequence above should therefore try to access FFFFFFFF on the fifth cycle.
This would seem the next step to me. If something's pulling the lines low, or talking on the data bus, you might be seeing this kind of thing.
Good luck,
BW.
DFB1 Open source 50MHz 030 and TT-RAM accelerator for the Falcon
DSTB1 Open source 16Mhz 68k and AltRAM accelerator for the ST
Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
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DSTB1 Open source 16Mhz 68k and AltRAM accelerator for the ST
Smalliermouse ST-optimised USB mouse adapter based on SmallyMouse2
FrontBench The Frontier: Elite 2 intro as a benchmark
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- Posts: 19
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Re: I need your help for my Falcon030
Thanks a lot for your help I’ll try to remove rom and watch the result. I’ll give you the result. Thanks
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Re: I need your help for my Falcon030
When i remove the rom, i get $FFFF as Data. It's good. But, now, the cpu doesn't continue after reading $000004.... It stops after reading