Re: [Qemu-devel] [PATCH] PC speaker emulation (fixed point)

2006-01-24 Thread Sebastian Kaliszewski
On Tuesday 24 January 2006 22:45, Fabrice Bellard wrote: > If you want to model the real PC speaker, the best to do is to generate > a square signal and to pass it thru a low pass filter with a cut off > frequency of a few kHz. Then you could even be able to play samples thru > the simulated PC spe

Re: [Qemu-devel] [PATCH] PC speaker emulation (fixed point)

2006-01-24 Thread Fabrice Bellard
Sebastian Kaliszewski wrote: Joachim Henke wrote: Ok, these are really strong arguments. Thanks a lot for your interesting statements! I'll do some testing on square waves and will post an updated patch, as I am also not totally satisfied with the current sound myself. One little sugges

Re: [Qemu-devel] [PATCH] PC speaker emulation (fixed point)

2006-01-24 Thread Sebastian Kaliszewski
Joachim Henke wrote: Ok, these are really strong arguments. Thanks a lot for your interesting statements! I'll do some testing on square waves and will post an updated patch, as I am also not totally satisfied with the current sound myself. One little suggestion... Real PC-speaker is rath

Re: [Qemu-devel] [PATCH] PC speaker emulation (fixed point)

2006-01-24 Thread Joachim Henke
Ok, these are really strong arguments. Thanks a lot for your interesting statements! I'll do some testing on square waves and will post an updated patch, as I am also not totally satisfied with the current sound myself. Sincerely Jo. Sebastian Kaliszewski wrote: Well, it sounds rather dul

Re: [Qemu-devel] [PATCH] PC speaker emulation (fixed point)

2006-01-24 Thread Sebastian Kaliszewski
Joachim Henke wrote: I still prefer using a sine wave, it sounds more smooth and won't hurt our ears (and speakers) too much. Well, it sounds rather dull, and even worse, on non hi-fi computer speakers (which is 90% of PC users use) low frequencies (<100Hz) are simply unhearable (since equip

[Qemu-devel] [PATCH] PC speaker emulation (fixed point)

2006-01-23 Thread Joachim Henke
I still prefer using a sine wave, it sounds more smooth and won't hurt our ears (and speakers) too much. I don't think that people want to play square waves, when they have their PC connected to their hifi system (c: The main purpose of the PC speaker is to generate tones and many programme

Re: [Qemu-devel] [PATCH] PC speaker emulation (fixed)

2006-01-20 Thread Johannes Schindelin
Hi, On Fri, 20 Jan 2006, Joachim Henke wrote: > Thanks for the hint! I assume, the reason, why floating point calculations > should be avoided, is to be compatible with processors like ARM, that don't > necessarily have an FPU. > > Yes, I'll rewrite the waveform generation stuff to fit in fixed

Re: [Qemu-devel] [PATCH] PC speaker emulation (fixed)

2006-01-20 Thread Sebastian Kaliszewski
malc wrote: I'd like to not one thing, namely, you are using FPU to generate the samples. This is something Fabrice expressed dissatisfaction with. In the case of speaker it might be feasible to switch to fixed-point calculation. One more note about that. PC-speaker generates just plain square

Re: [Qemu-devel] [PATCH] PC speaker emulation (fixed)

2006-01-20 Thread Joachim Henke
Thanks for the hint! I assume, the reason, why floating point calculations should be avoided, is to be compatible with processors like ARM, that don't necessarily have an FPU. Yes, I'll rewrite the waveform generation stuff to fit in fixed point. It should also be faster then. Jo. malc wrote:

Re: [Qemu-devel] [PATCH] PC speaker emulation (fixed)

2006-01-19 Thread malc
On Thu, 19 Jan 2006, Joachim Henke wrote: Thanks a lot for your help! I wasn't aware that AUD_write could return zero. Seems that I was just lucky, it didn't do that with 44100 Hz sample rate (c: You are welcome. Now it works fine with 32000 Hz, and I really encourage people (especially PC

[Qemu-devel] [PATCH] PC speaker emulation (fixed)

2006-01-19 Thread Joachim Henke
Thanks a lot for your help! I wasn't aware that AUD_write could return zero. Seems that I was just lucky, it didn't do that with 44100 Hz sample rate (c: Now it works fine with 32000 Hz, and I really encourage people (especially PC users) to test the attached patch. Call QEMU with the swi