Symbian emulator?

And emulating only the PSG? Would that work?

Well, now it's PSG and SCC(+). I didn't even try using the MIDI codec in Series 60...

The main problem with current phones (based on Symbian OS 6.1) is that audio streaming is not too well supported - handling the stream takes a lot of overhead which results in bursts of audio output. This is no problem if you are streaming a WAV for example, that has all the data in place. But in an emulator you need to be running the machine emulation at the same time to produce the input to generate the audio data in the first place. Now because the stream handling eats up processing time the machine emulation is not running at a constant speed anymore which then results in variation in the audio generation speed as well - which in turn can be heard as changing tempo =/

Yes it would be possible to code everything in assembler =) That would of course speed things up but it would not remove the problem with the audio stream handling -- in Symbian OS 6.1 applications cannot get direct access to the DSP (or even to the sound driver) so you would anyway be talking to the same media server process from your assembler code and it is exactly this communication which is not suitable for the emulator use case...

Why would you think I would know anything about that?

Ok, seriously, I know that this will not be possible.

Whatever you do, it's great, jr!! And take your time

Okay, it finally seems that there is no way to synchronize the emulation (and thus also the sound) correctly in current phones. This is because the highest accuracy in timing available for applications is 1/64s, at least in the currently available phones. That makes it a bit hard to sync to 50Hz for example since the exact time needed to emulate the machine for one vsync cannot be predicted and the Symbian OS system clock only gives you 1/64s accuracy. This means that in a delay loop you could then decide to wait one or zero clock ticks and there is a huge difference in which one you choose.

There is an undocumented function call in the kernel interface that would provide access to a high precision timer but unfortunately this does not seem to work in the current phones - it is only working in the Symbian OS emulator on PC. Too bad. With this function call I have everything running ever-so-smoothly in the Symbian OS emulator so if the function would work on the phone... well, you know.

So far I've been lucky to have the emulation running at approximately right speed but in reality it is not synchronized at all meaning that if the phone had more CPU power the emulation would be running too fast.

So if anyone knows any good algorithm to still achieve synchronization with the timer limitations that the system has, I would be happy to implement it. Or if someone knows of a way to access high precision timer on the phone, I would be more than happy to take advantage of it.