Note: OPF is MSX-DOS2 compatible. Really!

yes, but only after you do
"set expert on"

I didn't know till tonight

@ARTRAG That might happen if you don't format your disk with MSX-DOS2... Maybe it's time to update COMMAND2.COM to 2.41

COMMAND 2.41 ROCKS!!

@dvick, news on the analysis of the samples ?

Quote:

... Then I did a new replayer that is a one channel that resets the phase every 31.95 samples (to avoid getting out of sync) and then writes new samples in a way so they don't overlap with the played sample. The result was good (see the little demo in the post I'm soon about to make). This one is using syncrhonized code with busy loops that are made to fit the period as well as possible, somewhat similar to the poliphase player but this one only uses one SCC channel. ...

This gives me a strange feeling about the poliphase approach,
in the poliphase the synchronization is given by VINT.

Try to follow the same steps of the replayer that worked....

Set the period of ch1 in such a way that VINT arrives every 31.95 samples
At each VINT you need to resets the phase of ch1 and then write new samples
in a way so they don't overlap with the played sample.

If the result was good above, it should be good even in this case ....
Or not ?

Timing wise the two replayers are identical. Syncronizing to VINT or use a fixed length loop doesn't make a difference. Both resets the phase after 31.95 samples.

In the poliphase replayer the period is set based on VINT such that the reset happens every 31.95 samples

In the Leila K replayer I know the period and select the length of the busy loop so that the reset happens every 31.95 samples.

The only difference between the polyphase version and the Leila K replayer is that its updating four SCC channels instead of one and that the period is about 1/8 of the Leila K replayer (the latter has about 2x the sampling frequency).


Using a busy loop feels a bit more deterministic perhaps so I should try using a fixed size loop in the poliphase version and see if the result gets better. My first feeling was that the four channels may interfere with eachother, either while playing or when writing new sample data. I still hope its a timing issue that can be solved.

try one single channel first with one probe signal
than try two channels with two probe signals
should you need I sample for you,
send me the two roms (maybe less than 512K this time

Quote:

try one single channel first with one probe signal

Isn't this what the first replayer in this thread did (before the poliphase one)? That one actually also had noise problems.

Also this is what I did with the leila k replayer. I simply added probing of ch4 and it added noise.

sorry for being slow, our daughter has been a bit sick so I haven't had much time to create the test roms. But now they are ready. If you could load these and sample them it would be great. One is your triangle wave ARTRAG (but 8x the frequency) the second is my test signal as it should have been (also a triangle but called square in the zip )

http://www.bluemsx.com/demos/scctest.zip

I've sampled the files and sent them.
let me know

if you had the original wav files
i could guess to compare them

There are no original wav files (the data is generated with the little tool that you modified). I can try to generate real wav's from the raw data. I'm a bit busy atm but I'll do it as soon as possible.

I've an RGB cable that outs separate RCA video and audio, so
I can plug the audio RCA out to my laptop mic in using a converter.
Let me know if you need other experiments.

Any news ? this use of the SCC has a big potential,
dvik can i do something ?
(now I have a CF reader, a SCC flash with 512K and
an almost working TR)