; ***************************************************************************
; copyright   : (C) 2025 by Martin Preuss
; email       : martin@libchipcard.de
;
; ***************************************************************************
; * This file is part of the project "AqHome".                              *
; * Please see toplevel file COPYING of that project for license details.   *
; ***************************************************************************

#ifndef AVR_MODULES_COM2W_COM2WN_WAIT_H
#define AVR_MODULES_COM2W_COM2WN_WAIT_H


; WORK IN PROGRESS



.cseg



; ---------------------------------------------------------------------------
; @routine com2wWaitForClockHighMulti10Us
;
; Wait for high CLK
;
; @param  R20 multiple of 10us to wait (e.g. "2" for "20" us, max: 32)
; @return CFLAG set if okay (state reached), cleared on error
; @clobbers: r16, r20, r22

com2wWaitForClockHighMulti10Us:
.if clock == 8000000
  add r20, r20 ; *2
  add r20, r20 ; *4
  add r20, r20 ; *8
.endif
.elif clock == 1000000
; nothing to do
.else
  .error "Unhandled clock speed"
.endif

  ldd r22, Y+COM2W_IFACE_OFFS_PINMASK_CLK             ; +2
com2wWaitForClockHighMulti10Us_loop:                  ; 10 cycles per loop
    inr r16, COM_CLK_INPUT                            ; +1 (if low port, +2 if high port)
    and r16, r22                                      ; +1
    brne com2wWaitForClockHighMulti10Us_stateReached  ; +1 if FALSE, +2 if TRUE

    inr r16, COM_CLK_INPUT                            ; +1 (if low port, +2 if high port)
    and r16, r22                                      ; +1
    brne com2wWaitForClockHighMulti10Us_stateReached  ; +1 if FALSE, +2 if TRUE

    nop                                               ; +1
    
    dec r20                                           ; +1
  brne com2wWaitForClockHighMulti10Us_loop            ; +2 if TRUE, +1 if FALSE
  clc                                                 ; +1
  ret                                                 ; +4
com2wWaitForClockHighMulti10Us_stateReached:
  sec                                                 ; +1
  ret                                                 ; +4
; @end



; ---------------------------------------------------------------------------
; @routine com2wWaitForClockLowMulti10Us
;
; Wait for low CLK
;
; @param  R20 multiple of 10us to wait (e.g. "2" for "20" us, max: 32)
; @return CFLAG set if okay (state reached), cleared on error
; @clobbers: r16, r20, r22

com2wWaitForClockLowMulti10Us:
.if clock == 8000000
  add r20, r20 ; *2
  add r20, r20 ; *4
  add r20, r20 ; *8
.endif
.elif clock == 1000000
; nothing to do
.else
  .error "Unhandled clock speed"
.endif

  ldd r22, Y+COM2W_IFACE_OFFS_PINMASK_CLK             ; +2
com2wWaitForClockLowMulti10Us_loop:                   ; 10 cycles per loop
    inr r16, COM_CLK_INPUT                            ; +1 (if low port, +2 if high port)
    and r16, r22                                      ; +1
    breq com2wWaitForClockLowMulti10Us_stateReached   ; +1 if FALSE, +2 if TRUE

    inr r16, COM_CLK_INPUT                            ; +1 (if low port, +2 if high port)
    and r16, r22                                      ; +1
    breq com2wWaitForClockLowMulti10Us_stateReached   ; +1 if FALSE, +2 if TRUE

    nop                                               ; +1
    
    dec r20                                           ; +1
  brne com2wWaitForClockLowMulti10Us_loop             ; +2 if TRUE, +1 if FALSE
  clc                                                 ; +1
  ret                                                 ; +4
com2wWaitForClockLowMulti10Us_stateReached:
  sec                                                 ; +1
  ret                                                 ; +4
; @end










#endif ; AVR_MODULES_COM2W_COM2WN_WAIT_H