Darrels interrupts and multiple SOUND statements, will it work?

[HenrikOlsson]

Hi,
2.2kHz (Output_x = 28835) should work. The higher you go the more jittery the output becomes.

If you want to calculate the value to put in the Output_x variables at runtime (instead of using a lookup table or whatever) you can do it with Output_x = ( Frequency + ( Frequency ** 20353 ) ) where Frequency is a WORD containing the desired output frequency * 10, (4400 = 440.0Hz)

It's not perfect but may be good enough.

Let me know if you get around to trying it.

/Henrik.

[CuriousOne]

What happens if I run this code say at 4mhz 16F870 ? there will be no output, frequency wont match, or sound will be breaking up?

[CuriousOne]

on 16F876A, gives error during compile on this:

IPR1.1 = 1 ' TMR2 high priority

[CuriousOne]

Gives same error on 12F1840.

[HenrikOlsson]

Hi,

> What happens if I run this code say at 4mhz 16F870 ? there will be no output, frequency wont match, or sound will be breaking up?

There's not enough time to actually execute the interrupt service routine before the timer fires another interrupt. The CPU will spend all of its time in the ISR, no time left for you to set the desired frequencies etc and the output frequenices will be wrong and...... Simply - It just won't work. You need 16MHz.

> on 16F876A, gives error during compile on this:
> IPR1.1 = 1 ' TMR2 high priority

The 16F series doesn't have interrupt priorities, remove the line.

> Gives same error on 12F1840.

The 12F series doesn't have interrupt priorities, remove the line.

/Henrik.

[CuriousOne]

Still does not compile on 16F876A -

ASM ERROR:
Symbol not previously defined (wsave), (ssave), (psave).

Compile OK on 12F1840, but ASM warning - Found label after column 1. (Generate), Extraneous arguments on the line

[CuriousOne]

added this for 16F876A:

wsave VAR BYTE $20 SYSTEM
ssave VAR BYTE $22 SYSTEM
psave var byte $24 SYSTEM

Have no idea why, but no more errors in compile, will try runtime shortly.

[CuriousOne]

It works, sort of (20mhz crystal 16F876A).

If any channel duration has same value, these channels won't play.
Also, playback duration is different each time, it might play 4 or 5 times same duration, then 2 times shorter duration, then again normal.
It works properly only when value of output timings is first is the shortest, 2nd medium and 3rd - longest. If in reverse, it will only play last, short one.