HI Jallians,
Here is ' first release' of my library for playing music with hardware PWM from 877. Fell free and happy to use it in your projects. 877 must be clocked at 4MHz, only two octave are included here. I'm working now for variable notes length ( 1, 1/2, 1/4, 1/8, 1/16 ) Some simple ideas are welcome !
Wouter, playing with banks in JAL is painful ! Help us, although we gone die...
-- libraries
include f877_04
include jpicm -- a modified jpic library for 877 registers
include jdelay
-- config pins
-- var bit pwm1 is pin_c2
-- pin_c2_direction = output
-- procedure tempo ( byte in flow ) is
var byte lenght = 10
var byte pause
pause = lenght / 2
-- end procedure
procedure frequency ( byte in period, byte in prescale ) is
asm movf period, w
bank_1
asm movwf f877_pr2
bank_0
f877_ccpr1l = period / 2 -- set duty cycle at approx 0.5
pin_c2_direction = output -- output the waves
if prescale == 16 then
f877_t2con = 0b_0000_0110 -- tmr2 on, prescale=16
elsif prescale == 4 then
f877_t2con = 0b_0000_0101 -- tmr2 on, prescale=4
elsif prescale == 1 then
f877_t2con = 0b_0000_0100 -- tmr2 on, prescale=1
end if
f877_ccp1con = 0b_0000_1100 -- pwm mode on
end procedure
procedure stop is
delay_100mS ( lenght )
f877_ccp1con = 0 -- PWM off
delay_100ms ( pause )
end procedure
procedure DO1 is frequency ( 238, 16 ) stop end procedure
procedure REb1 is frequency ( 224, 16 ) stop end procedure
procedure RE1 is frequency ( 212, 16 ) stop end procedure
procedure MIb1 is frequency ( 200, 16 ) stop end procedure
procedure MI1 is frequency ( 189, 16 ) stop end procedure
procedure FA1 is frequency ( 178, 16 ) stop end procedure
procedure FAd1 is frequency ( 168, 16 ) stop end procedure
procedure SOL1 is frequency ( 158, 16 ) stop end procedure
procedure LAb1 is frequency ( 149, 16 ) stop end procedure
procedure LA1 is frequency ( 141, 16 ) stop end procedure
procedure SIb1 is frequency ( 133, 16 ) stop end procedure
procedure SI1 is frequency ( 126, 16 ) stop end procedure
procedure DO2 is frequency ( 118, 16 ) stop end procedure
procedure REb2 is frequency ( 112, 16 ) stop end procedure
procedure RE2 is frequency ( 105, 16 ) stop end procedure
procedure MIb2 is frequency ( 99, 16 ) stop end procedure
procedure MI2 is frequency ( 94, 16 ) stop end procedure
procedure FA2 is frequency ( 88, 16 ) stop end procedure
procedure FAd2 is frequency ( 83, 16 ) stop end procedure
procedure SOL2 is frequency ( 79, 16 ) stop end procedure
procedure LAb2 is frequency ( 74, 16 ) stop end procedure
procedure LA2 is frequency ( 70, 16 ) stop end procedure
procedure SIb2 is frequency ( 66, 16 ) stop end procedure
procedure SI2 is frequency ( 252, 4 ) stop end procedure
procedure DO3 is frequency ( 238, 4 ) stop end procedure
-- main program
forever loop
DO1 REb1 RE1 MIb1 MI1 FA1 FAd1 SOL1 LAb1 LA1 SIb1 SI1 DO2
delay_1S ( 3 )
DO1 RE1 MI1 FA1 SOL1 LA1 SI1 DO2
delay_1S ( 3 )
DO2 RE2 MI2 FA2 SOL2 LA2 SI2 DO3
delay_1S ( 3 )
DO1 MI1 SOL1 DO2 DO2 SOL1 MI1 DO1
DO2 MI2 SOL2 DO3 DO3 SOL2 MI2 DO2
delay_1S ( 3 )
end loop