Ringtones article on BeyondLogic

[gil]

There's an aritcle at beyondloginc which explains how to work the PIC16F876 to output ringtones.

Does anyone knows if it would be possible to implement it on a PIC16F684?
(Of courese some changes will be required in the code)

 

[Nigel Goodwin]

There's an aritcle at beyondloginc which explains how to work the PIC16F876 to output ringtones.

Does anyone knows if it would be possible to implement it on a PIC16F684?
(Of courese some changes will be required in the code)

A quick look at the datasheet for the 684 shows it has the two timers required, so there should be very little code change required - only slight changes may be needed to the setup code - both use the same 14 bit core.

 

[gil]

I have made what i believe to be the required code changes and my circuit still doesn't work (i don't think the circuit needs any modifications).
I set RA2 to output instead of RB0 in the original code.
All i'm getting is clicks on the speaker which appear to be the right timing but no sound.
Is there any other setup code I need to modify?

 

[Nigel Goodwin]

I have made what i believe to be the required code changes and my circuit still doesn't work (i don't think the circuit needs any modifications).
I set RA2 to output instead of RB0 in the original code.
All i'm getting is clicks on the speaker which appear to be the right timing but no sound.
Is there any other setup code I need to modify?

I don't write C, but it looks to me like timer1 interrupts are generating the actual tone, and timer0 interrupts are doing the timing. As you're getting a click, but no tone, I would suggest looking around the timer1 code.

 

[gil]

thanks, im looking into that area - what do you think should be the main configuration for the oscillator?

 

[Nigel Goodwin]

thanks, im looking into that area - what do you think should be the main configuration for the oscillator?

It's a 20MHz crystal, so it needs setting to HS.