STE video chip

[exxos]

So it was the track width was to large to "snap to" the pad

Capture.JPG (61.04 KiB) Viewed 2912 times

[exxos]

So JLC do not do panelized assembly on small boards

Capture (1).JPG (21.52 KiB) Viewed 2896 times

If I put panel by customer, it still moans that the board diameter is too small.

My workaround for this previously is to just deliberately make the board larger and hacksaw it when it comes

[Steve]

If you ordered a few of these boards I wouldn't mind testing one in my out of phase STe if possible @exxos

[exxos]

If you ordered a few of these boards I wouldn't mind testing one in my out of phase STe if possible @exxos

Once I get one tried in my own STE and it fixes the problem, I'll send you one to see if it solves your problem as well.

[Steve]

Cheers!

[fenarinarsa]

Hello everyone,

I ran into an issue that may or may not be related to your findings.

Last month I released a VGA intro for Mega STE + ET4000 video card https://demozoo.org/productions/303160/
The sound is made of PCM audio data streamed from the hard drive.

However I had many audio bugs (audio cracks), which didn't come from my code because I disabled the audio streaming and played back looping empty buffers and the cracks were still there.

I use the blitter to transfer data through the VME bus and I also found out that transferring data with the CPU reduced drastically the number of audio cracks (a few to none, actually).

On Atari forum I was told about a known DMA bug with some Mega STE shifters. It looks there was various revisions of the C301712 because the earlier ones had this DMA audio bug on MSTE. So I tried to swap the shifter with one of my STE's.

shifter.jpg (285.38 KiB) Viewed 2803 times

The Mega STE original shifter is the C301712-001 and the STE shifter is C300588-001

Putting the C300588 into my Mega STE made the DMA audio issue completely disappear. However Idek on Atari-forum tried the same swap and it didn't make the audio bug disappear on his setup.

I just put the C301712 into my STE and I was expecting the graphic issues that you posted here, but so far everything works perfectly. I think this STE is one of the early TOS 1.62 ones, with three ICs in the middle (no more 2+piggyback patch) and external blitter.

just FYI

[exxos]

Thanks for pointing this out. If you have a simple audio program to use, then next time I have the STE connected up I can see if audio gets trashed. I would assume so.

While I've known about those problem chips for a long time, I never thought anything much of it. There could be other factors at play as well. But it's probably down to tolerances on every machine. Some it works fine on, some not. The version of combo could be a factor for example.

[fenarinarsa]

Thanks for pointing this out. If you have a simple audio program to use, then next time I have the STE connected up I can see if audio gets trashed. I would assume so.

Here you go https://github.com/fenarinarsa/ste_dmatest/releases/

Tested on my Mega STE with the faulty C301712 and the audio cracks/clicks can be heard clearly.

[exxos]

Here you go https://github.com/fenarinarsa/ste_dmatest/releases/

Tested on my Mega STE with the faulty C301712 and the audio cracks/clicks can be heard clearly.

Thanks, will try and test it out tomorrow.

[fenarinarsa]

Well, I've just tested the C301712 on my STE with my tool and I can also hear audio cracks. I guess putting it into my STE doesn't fix anything then.