Re: [hatari-devel] Regression in 2.0.0 RC1

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On Fri, 28 Oct 2016, Nicolas Pomarède wrote:

Apart from that, here're some things that could be measured on STE :

- set start=end, start dma sound with repeat off : does dma turns off immediately or at the end of the next video line where FIFO would be filled ?
Do we get the "end of frame" timer A interrupt in that case ?
I guess dma sound counter and bit 0 of ff8901 are updated at the end of each line, when display enabled is set to off and shifter displays border color.

Hello,

I tested this; set start and end the same, and start replay without loop. I've also initialized Timer A in event mode to invert background colour if it happens. I set event to 1 so it will interrupt after the first loop.

Results:

- Hatari 2: noise played, no inverted background
- STe: silent, no inverted background


- if start=end and we start dma sound with repeat on, do we also get an immediate end of frame timer A interrupt, just before dma address goes beyond end address ? As the end condition seems to not be correctly checked in that case, maybe the end of frame bit in the MFP is not available either and we would not get an input on timer A in event count mode ?

So the same program as above, but with loop.

- Hatari 2: noise played, no inverted background
- STe: a tiny click then silence, no inverted background

So it would seem with repeat the STe does play a little bit of data before shutting off.

Maybe I did some mistake in the code, here it is for both tests:
http://ae.dhs.nu/tmp/hdma2.zip

--
Anders Eriksson
ae@xxxxxx     http://www.dhs.nu/
ae@xxxxxxxxx  http://www.atari.org/


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