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Re: Issue writing data on floppy (Write protected)

Posted: 03 Feb 2021 19:08
by exxos
Its the 2 1K resistors in the middle of the board.. it may help with floppy, but not so sure about US.

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Re: Issue writing data on floppy (Write protected)

Posted: 03 Feb 2021 19:53
by geogeo_28
I will give a try. Thanks exxos.

The thing is, I have no more issues with the floppy. Looks fine at 8/32MHz with a real floppy drive or Gotek.
I ran extensive read/write using the diagnostic cartridge floppy/disk exerciser for 50 cycles and no errors.

The remaining problem is data corruption on UltraSatan.
Weird as its sound, everything is rock solid at 32 MHz. UltraSatan corruptions happened at 8 MHz.
I can record a small video to show it.

That's why I am able to create partitions on the SD at 32 MHz and debug at 8MHz by creating folders.

Re: Issue writing data on floppy (Write protected)

Posted: 03 Feb 2021 20:45
by exxos
geogeo_28 wrote: 03 Feb 2021 19:53 Weird as its sound, everything is rock solid at 32 MHz. UltraSatan corruptions happened at 8 MHz.
I can record a small video to show it.
It doesn't make any sense though, as booster runs at 8MHz during DMA cycles anyway.

Re: Issue writing data on floppy (Write protected)

Posted: 04 Feb 2021 12:18
by Steve
@geogeo_28

FYI I am also troubleshooting an old STE mobo that looks identical to yours. Same corruption at 8mhz but fine at 32mhz.

https://www.exxosforum.co.uk/forum/viewt ... =18&t=3902

I've pretty much done the same as you, except my DMA pullups are 10k on the WD1772, and none on the actual DMA chip. (as afaik you should just do one or the other)

Re: Issue writing data on floppy (Write protected)

Posted: 04 Feb 2021 20:09
by geogeo_28
Oh I feel less alone :)
Thanks Steve!

Re: Issue writing data on floppy (Write protected)

Posted: 05 Feb 2021 00:25
by exxos
Have you tried running emutos from floppy to see if you still get corruption ?

Re: Issue writing data on floppy (Write protected)

Posted: 06 Feb 2021 07:15
by geogeo_28
exxos wrote: 05 Feb 2021 00:25 Have you tried running emutos from floppy to see if you still get corruption ?
Here it is:

Re: Issue writing data on floppy (Write protected)

Posted: 06 Feb 2021 09:58
by exxos

Re: Issue writing data on floppy (Write protected)

Posted: 07 Feb 2021 23:07
by geogeo_28
Just tested this software on ASCI ID 0 and obtain a bunch of '*'.
No read/write error. :/
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Re: Issue writing data on floppy (Write protected)

Posted: 07 Feb 2021 23:12
by exxos
geogeo_28 wrote: 07 Feb 2021 23:07 Just tested this software on ASCI ID 0 and obtain a bunch of '*'.
No read/write error. :/
This has all the signs of noise then... I'm not sure there will be a solution other than change the STE motherboard and start again. Diagnosing such faults can take a incredible amount of time and it pretty much always comes back to the bad grounding on the motherboard itself. Such faults appear quicker than I can diagnose them, it's why I gave up with it all and started with a new motherboard.