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Re: v2 Analog - Apple ][ VGA adapter build
Posted: 13 Apr 2023 11:55
by rubber_jonnie
Ok, so first try and something isn't quite right...
First off, I get a clear and sharp splash screen:

- PXL_20230413_103404153.jpg (319.42 KiB) Viewed 1350 times
So the RPi Pico is clearly working with the correct firmware, but once the machine boots, that's when things go a bit wonky, as is evidenced by Elite:

- PXL_20230413_103700002.jpg (295.49 KiB) Viewed 1350 times
If I boot to something 'Texty' like ProDos, the main screen looks like this:

- PXL_20230413_104515160.jpg (231.75 KiB) Viewed 1350 times
And the VGA looks like this:

- PXL_20230413_104519881.jpg (258.49 KiB) Viewed 1350 times
There is a 'However' here though.
From what I understand there is a config program, something which I don't yet have a disk image for, so it may well have started in an incorrect mode (I think Adrian Black suggested this) so I need to find that and see how it all pans out before I start troubleshooting, but so far I'm reasonably happy with what's what.
Re: v2 Analog - Apple ][ VGA adapter build
Posted: 13 Apr 2023 12:30
by PhilC
@rubber_jonnie that looks like a very good start.
Re: v2 Analog - Apple ][ VGA adapter build
Posted: 13 Apr 2023 13:16
by rubber_jonnie
PhilC wrote: 13 Apr 2023 12:30
@rubber_jonnie that looks like a very good start.
Yeah, I think I'm pretty close TBH, just need the damn config software!!
Re: v2 Analog - Apple ][ VGA adapter build
Posted: 13 Apr 2023 17:38
by Tomswork
@rubber_jonnie
Is this the machine that has the 80 column card problem ?
Tom
Re: v2 Analog - Apple ][ VGA adapter build
Posted: 13 Apr 2023 19:59
by stephen_usher
That looks suspiciously like a one bit error on the address bus.
Re: v2 Analog - Apple ][ VGA adapter build
Posted: 13 Apr 2023 22:09
by rubber_jonnie
Tomswork wrote: 13 Apr 2023 17:38
@rubber_jonnie
Is this the machine that has the 80 column card problem ?
Tom
It is...
However the card needs to be configured and I don't yet have the software.
Re: v2 Analog - Apple ][ VGA adapter build
Posted: 13 Apr 2023 22:11
by rubber_jonnie
stephen_usher wrote: 13 Apr 2023 19:59
That looks suspiciously like a one bit error on the address bus.
Yes, quite possibly, but I need to configure the card first and I can't find the software anywhere.
I think the MMU may be getting worse too, as I'm starting to get errors at other times too, even with the 80 column card removed.
I could really do with another Apple II or IIe for testing.
Re: v2 Analog - Apple ][ VGA adapter build
Posted: 14 Apr 2023 00:16
by Tomswork
@rubber_jonnie
I'm not sure if the mmu from the ntsc systems work in the pal machines i have 2e board for spare parts will have to check the part numbers. This cards slots do have buffers on them ? The memory read for the vga card is the same over lap as the system memory base 16k i believe
Tom
Re: v2 Analog - Apple ][ VGA adapter build
Posted: 14 Apr 2023 08:29
by PhilC
@rubber_jonnie id love to help with you fixing your machine but would be worried about me breaking mine too.
Re: v2 Analog - Apple ][ VGA adapter build
Posted: 14 Apr 2023 09:35
by rubber_jonnie
Ok, so
@PhilC @Tomswork as ever I appreciate your input!!
If you could have a look at the MMU I'd be grateful Tom, this is the part I have:

- PXL_20230414_081924754~3.jpg (225.3 KiB) Viewed 1269 times
However I think you're right in that the NTSC and PAL parts are different.
Phil, no worries, I appreciate your offer but wouldn't ask you to put your machine in peril for mine.
However, I have good news regarding the VGA card. I spoke to the dev overnight via Github and he suggested that I check for solder bridges. I did, (I also did when I built it) and there weren't any, but I did find 2 loose pins. Now I'm sure I checked for loose pins, but I obviously missed these two, which were on 2 different level shifters.
So, I have resoldered them and it only bloody works!!! The picture is nice and sharp too :)

- PXL_20230414_081032380.jpg (275.99 KiB) Viewed 1269 times

- PXL_20230414_080951637.jpg (323.58 KiB) Viewed 1269 times

- PXL_20230414_080922048.jpg (236.64 KiB) Viewed 1269 times
I also believe that the problems I had with the base machine are most likely due to condensation after using the freeze spray again, so I'm going to avoid it for now and just test the base machine with the VGA card and avoid mucking around with the MMU.