GP32 Cpu Speed Questions


ConsoleTom

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Hi !

I would like to know, what does the 2nd and 3rd value do ?

GpClockSpeedChange(132000000, 0x24001, 2); /* speed = 133 Mhz */

What speeds are allowed ? Are there special values, or could i set it to 12222222 for example ? (I need a speed that has a nice value to the next question)

And now i need some possibility to calculate a BPM (Beats per Minute) speed, so: how many ticks are one second (i know, i asked it some time ago) at 133 Mhz / 66 Mhz ?

Drums and BPM ? Guess what i want to do ! B)

Greetings

Tobias
 
> GpClockSpeedChange(132000000, 0x24001, 2); /* speed = 133 Mhz */


Please search the forum, there are a lot threads, discussing this...

>And now i need some possibility to calculate a BPM (Beats per Minute) speed, >so: how many ticks are one second (i know, i asked it some time ago) at 133 >Mhz / 66 Mhz ?

You cant calculate your BPM from the CPU clockrate, use the Sound Output Freq, as a Base. ( e.g. 44.100Khz )
means 44100 Samples/seconds.

One Sample is 16 Byte Stereo = 44100*2*2 Bytes/ second
 
Hi !

Thanks. I'll search the forum.

But i didn't mean bytes per minute but beats that define the speed of a song for example.

For the solution of the problem i just have to found out how many ticks are one second.

Greetings

Tobias
 
ConsoleTom posted on May 19 2004 at 01:23 PM said:
Hi !

Thanks. I'll search the forum.

But i didn't mean bytes per minute but beats that define the speed of a song for example.

For the solution of the problem i just have to found out how many ticks are one second.

Greetings

Tobias
Once again, you cant calculate your Beats per Minutes from the Tick of the CPU clock...

You can playback a Sample with 100 BPM with 133 or 66Mhz or 33Mhz...

If your Samplerate is 44100 Hz, and you want a 100 BMP drumloop,
= 100/60 = 1.6 beats per seconds
-> means you need a waveform ( sine/rectangle ) changing every (44100/1.6) = 26500 samples.
 
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Mirko, I think you misunderstood him here... He's not talking about playing a 100bpm LOOP, he wants to play samples fitting to a specified speed, like 120bpm = max. 2 samples in 1 second, like [Bassdrum] <-0.5 sec pause-> [HiHat] <-0.5 sec pause-> [Snare] and so on.
 
don posted on May 19 2004 at 05:52 PM said:
Mirko, I think you misunderstood him here... He's not talking about playing a 100bpm LOOP, he wants to play samples fitting to a specified speed, like 120bpm = max. 2 samples in 1 second, like [Bassdrum] <-0.5 sec pause-> [HiHat] <-0.5 sec pause-> [Snare] and so on.
Hi !

That's right.

Tobias
 
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