DMA ISSUE ON H4

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exxos
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Re: DMA ISSUE ON H4

Post by exxos »

PaulJ wrote: Mon Dec 23, 2019 4:25 pm You are correct. The Ultra Satan works fine. The Atari test board fails while is passes on every other Atari machine I have. I'm going to complete the second H4 and see what happens there. If the second H4 also fails the DMA test I will look into it.
Maybe the buggy DMA tester is buggy :lol:
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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PaulJ
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Re: DMA ISSUE ON H4

Post by PaulJ »

exxos wrote: Mon Dec 23, 2019 4:34 pm
PaulJ wrote: Mon Dec 23, 2019 4:25 pm You are correct. The Ultra Satan works fine. The Atari test board fails while is passes on every other Atari machine I have. I'm going to complete the second H4 and see what happens there. If the second H4 also fails the DMA test I will look into it.
Maybe the buggy DMA tester is buggy :lol:
I doubt it since I've run it on 5 other machines which all pass. What ever it is is minor but it is nice to have something that makes a definitive call. What sucks is there software. Really doesn't tell you what is in error. Very terse error code then tells you to change all the chips. If the second H4 fails I will se if I can determine what it is unhappy with. Would be a nice project to disassemble the test cart code, add some actual definition to failures and transplant some of the tests to diagrom.
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exxos
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Re: DMA ISSUE ON H4

Post by exxos »

@PaulJ Do you have a close up image of the test board showing the chips used on the thing ? Also is it a original kit or a repo ? What DMA chip is being used ?
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viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
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People should find solutions to problems, not find problems with solutions.
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PaulJ
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Re: DMA ISSUE ON H4

Post by PaulJ »

@exxos ,see pic.. It also has circuitry to test parallel interface, and joystick interfaces.
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exxos
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Re: DMA ISSUE ON H4

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PaulJ wrote: Thu Dec 26, 2019 10:19 pm @exxos ,see pic.. It also has circuitry to test parallel interface, and joystick interfaces.
Thanks. Have you put the diag-cart in a DMA loop test and scoped out all the lines on the DMA port ? A1 has caused no end of trouble on STFM's.
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.
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PaulJ
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Re: DMA ISSUE ON H4

Post by PaulJ »

@exxos , No since the ultra satan was working I didn't devote much time since I wanted to get the H2 #2 working. Plan on getting back to it though since it passes with all the other atari's.
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Re: DMA ISSUE ON H4

Post by PaulJ »

@exxos , just ran all the diagcart tests on H4-2 and everything passes except the parallel port. The DMA test passes on this board and I also put in the glitter out of the remake which passes. So I guess there may be some issue with the DMA on the H4-1.
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Re: DMA ISSUE ON H4

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exxos wrote: Sun Dec 08, 2019 10:28 pm This is the draft of the patch board.
52C5FD20-E57E-4B8A-8A77-A8B5D8C67CE8.jpeg
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C2F206D0-F87D-4B9B-B3A5-9EE8FFA7632B.jpeg
C2F206D0-F87D-4B9B-B3A5-9EE8FFA7632B.jpeg (65.78 KiB) Viewed 4988 times
For completeness, this fix is tested and works for me.
Atari Falcon 030 | Atari 1040 STE | Atari 1040 STFM | Atari 1040 STF | Kryoflux & Supercard Pro Flux boards
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Re: DMA ISSUE ON H4

Post by rubber_jonnie »

@exxos Ok, just to ensure I'm understanding the patch board correctly, it fits in the socket for the 74LS245 and inverts the FDCS signal going to pin 19 of the 245? I presume the FDCS signal is taken from the DMA chip directly since the patch board does not allow the original FDCS signal to route from the DMA chip?

I just want to understand before I go and build one of these things.

Ta.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
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Icky
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Re: DMA ISSUE ON H4

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rubber_jonnie wrote: Wed Mar 11, 2020 11:25 pm @exxos Ok, just to ensure I'm understanding the patch board correctly, it fits in the socket for the 74LS245 and inverts the FDCS signal going to pin 19 of the 245? I presume the FDCS signal is taken from the DMA chip directly since the patch board does not allow the original FDCS signal to route from the DMA chip?

I just want to understand before I go and build one of these things.

Ta.
Thats correct @rubber_jonnie you can tap FDCS line from pin 19 of the other 74LS245 IC5 above it.
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