Re: [hatari-devel] MIDI support for Windows & OSX (with PortMidi)

[Nicolas Pomarède <npomarede@xxxxxxxxxxxx>]

Le 03/10/2017 à 21:26, David Savinkoff a écrit :
> ----- Eero Tamminen wrote:
>
> > PS. Jari has also some questions about jitter he's seeing in MIDI output:
> > 	http://www.atari-forum.com/viewtopic.php?f=51&t=32344
>
> As a MIDI jitter testing experiment, try the following sound options:
> --sound-buffer-size 10
> --sound-sync true
>
> These options affect emulation rate, and may improve the jitter.

Hi

I'm not sure this would help ; for midi output, you'd want as realtime 
possible behaviour, which I think is better achieved when emulation 
speed is not audio driven but using usleep in the main loop.
In that case if MFP expects a timer to last 1.39 sec for example under 
STF, then Hatari should take also exactly 1.39 sec.

Plus, MIDI programs don't necessarily use the YM2149 chip, so you would 
have no audio data to sync with (except playing empty audio buffers).

Put another way, I have more trust in usleep precision in that case than 
in syncing with an audio driver whose latency might vary depending on 
output sample rate or buffers size :)

Nicolas