Original post by APRULES2
Hi,
I was playing with the print chr$(7) command and I noticed no matter the number I put after the sound never changes I cant remember how to change the octives. Does anyone remember how?
Original post by Anders Carlsson
I don't think you can? That is a bell implemented by a summer, not programmable AFAIK. To get more musical sounds out of a PET, there is a hack one can build for the userport.
Original post by pet1978
To create sound you need to set values in the 6522 VIA chip using poke commands.
poke 59467,16 sets the shift register to free run, 0 to turn off sound
poke 59466,d loads the shift register. d should be 15,51 or 85 for square wave
poke 59464,c sets the shift rate. C is an integer from 0 to 255
frequency = 500000/(c*d1) where d1=8 for d of 15, d1=4 for d of 51, d1=2 for d of 85
So try:
10 poke 59467,16 : poke59466,51
20 for t = 1 to 12
30 read c : poke59464,c
40 for y = 1 to 100 : next
50 next t
60 poke59467,0
70 data 237,211,188,177,157,140,124,117,104,93,88,78