CD32 reset boot up fault

[Amiga1992]

YEah that issue with corruption on the Logo screen looks similar to issues I was having when connecting a TF328, maybe there's a higher problem here with the RAM or the ROM.

[trolleymaster]

thanks Akira

would that be the kickstart ROM ?
if so, I suppose thats the easiest place to start ?

[th4t1guy]

I wonder if the cd drive itself may be the problem?
Those compilation discs are usually filled with data, same with audio cds. Maybe the problem is related to being able to read the disc properly when the laser is further out on the track?

You might test with discs with different amounts of data written and see if that makes a difference (i.e. music cd with only 10 minutes or so on it).

[trolleymaster]

thanks for that th4t1guy

I dont think thats the main problem - the issue occurs without any cd in the drive anyway.

Ive run the diagnostics cd that supaduper recommended, and it shows the attached warning. does it mean anything ?

[xArtx]

Lisa is a video chip that would seem to relate to your logo problem.
It looks like one or more bitplanes are missing out of that area, and would have suspected memory there,
but it appears Lisa is supposed to send ID as does Gayle, so I’d be looking around that.

[jotd]

Snapshot from WinUAE (sorry for the white border, MSPaint sucks when you want to crop)



If you check the logo on WinUAE you get what looks like an "interlace" effect, invisible on a TV, visible on a monitor.

The logo "corruption" is a false lead imho. Unless WinUAE needs recapping

[trolleymaster]

Originally Posted by xArtx

Lisa is a video chip that would seem to relate to your logo problem.
It looks like one or more bitplanes are missing out of that area, and would have suspected memory there,
but it appears Lisa is supposed to send ID as does Gayle, so I’d be looking around that.

Don't suppose you know whereabouts on the schematic I need to be looking for that ID ?

[xArtx]

You can’t see ID registers without writing some software to address them.
Gayle ID for example is at about 0xDE0xxx IIRC.
I meant looking around the chip physically, or the chip itself.

But there could still be any number of problems, such as a RAM or ROM area, or even an upper address bus bit.

[xArtx]

It doesn’t look to me like what WinUAE does, but you can take a look.
The palette may not be the same here, but the data is.

[Amiga1992]

Originally Posted by jotd

The logo "corruption" is a false lead imho. Unless WinUAE needs recapping

What he showed in pictures is capture from a real CD32 and doesn't look like interlacing artifaction at all. Compare the two.
Also reporting "bad Lisa ID" is weird. Maybe there is a problem here with the video chip, or related video memory.

I'll take a little video of mine booting up, my TV shows interlacing artifaction on it, to prove it's nothing like what the OP is showing in his pics.

Did you manage to run a full memory scan?

[trolleymaster]

Hi

I ran all the memory tests possible, each one for about 5 hours. They all seemed fine and didn't report any errors.

its got me stumped !

[trolleymaster]

solved !

turns out it was the shift register chip 74LS166 (U34)

hope that helps someone else in future.