Video problem on STE

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Strider
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Video problem on STE

Post by Strider » Mon Mar 12, 2018 9:32 pm

Hello,

Yesterday I've recapped the PSUs of my 2 STEs.
I attached a photo, the PSUs have been controlled before starting the STEs.

However I have some video problems with these demos showing "true colour" pictures.
Here is an example:



My 2 STEs have the same problem. I also try swapping the PSUs, no difference.
What could be the issue?
Voltage?
I measured 5.2v and 12.16v on the output. Is it too high?
Thanks.
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exxos
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Re: Video problem on STE

Post by exxos » Mon Mar 12, 2018 9:54 pm

Can you post the program you are using and I can test it on one of my machines.
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

Strider
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Re: Video problem on STE

Post by Strider » Mon Mar 12, 2018 10:11 pm

Yes, this one: https://demozoo.org/productions/180989/
Here is the direct link if you have a hard disk: http://files.dhs.nu/files_demo/wonworld11_hd.zip
or a floppy disk: http://files.dhs.nu/files_demo/wonworld11_dd.zip (needs a MSA to disk conversion though)

I tried to lower the 5V, now it is 5.01V instead of 5.20V, but it makes no difference, video is still buggy.

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exxos
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Re: Video problem on STE

Post by exxos » Mon Mar 12, 2018 10:46 pm

OK I can confirm same problem.. I get corruption down the right side as well as "random" corruption in the image...

IMG_2350.JPG
IMG_2350.JPG (5.85 MiB) Viewed 362 times

My first thought of a "fix" and I got this...

IMG_2351.JPG
IMG_2351.JPG (6.11 MiB) Viewed 362 times

The image still seems to have some corrupt pixels.. but its not flicking corruption (might just be bad image data?)

.. and for the next step.. what value resistor pack do you have for P100 (just in front of the blitter)..?
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

Petari
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Re: Video problem on STE

Post by Petari » Tue Mar 13, 2018 8:04 am

This type of corruption can be caused because SW is made on/for STE with different CPU clock, and even if it is very small diff. it causes errors with high-color displaying. Wakeup state may affect things too. So, maybe to try to turn off machine couple times and retest.
Don't see that author gave exact description of HW on which they developed it.

Strider
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Re: Video problem on STE

Post by Strider » Tue Mar 13, 2018 6:20 pm

exxos wrote:
Mon Mar 12, 2018 10:46 pm
The image still seems to have some corrupt pixels.. but its not flicking corruption (might just be bad image data?)

.. and for the next step.. what value resistor pack do you have for P100 (just in front of the blitter)..?
Before modifying the PSUs I had those corrupt pixels. But never had the flicking corruption.

The P100 shows "M9-1-122J130" on one of my STE.
On the second STE the right part of the P100 is hidden by the blitter, all I can read is "MP-1-122J0.."
Some pictures:
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STE2.jpg
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STE1.jpg
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exxos
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Re: Video problem on STE

Post by exxos » Tue Mar 13, 2018 7:12 pm

Strider wrote:
Tue Mar 13, 2018 6:20 pm
The P100 shows "M9-1-122J130" on one of my STE.
On the second STE the right part of the P100 is hidden by the blitter, all I can read is "MP-1-122J0.."
Some pictures:
Odd.. The macine I tested has corruption, but 10K pull ups, when UDS has 1K on it, the problem goes away.. so 1.2K you have should work..

I also found swapping the CPU for a 68HC00 also solved the problem , so you could try that ( cue bad DMA thread again :roll: )
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

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