It's in there ... about 1/4 the way through.
Code:
;****************************************************************
;* HPWM       : Output a pulse width modulated wave in hardware *
;*                                                              *
;* Input      : W = channel 1 - 5                               *
;*            : R1 = frequency                                  *
;*            : R4 = duty cycle                                 *
;* Output     : None                                            *
;*                                                              *
;* Notes      :                                                 *
;****************************************************************