how about this as an example of a low frequency triangular wave:

loop:

for counter = 0 to 127
hpwm 1,counter,10000
pause 1
next counter

for counter = 127 to 0 step -1
hpwm 1,counter,10000
pause 1
next counter

goto loop

Of course all in PBP, not assembly, but this is a PBP forum as you may have observed.