; ***************************************************************************
; copyright   : (C) 2026 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 AQH_AVR_COMMON_INCCOUNTER32_ASM
#define AQH_AVR_COMMON_INCCOUNTER32_ASM



; ***************************************************************************
; code


.cseg


; ---------------------------------------------------------------------------
; @routine Utils_IncrementCounter32 @global
;
; Increment a 32 bit counter at the address given by X.
;
; @param X Address of the 4 byte counter (1. byte is LSB)
; @clobbers r18, r19, r20, r21, 22

Utils_IncrementCounter32:
  ld r18, x+
  ld r19, x+
  ld r20, x+
  ld r21, x
  ldi r22, 1
  add r18, r22
  clr r22       ; doesn't affect carry flag
  adc r19, r22
  adc r20, r22
  adc r21, r22
  st x, r21
  st -x, r20
  st -x, r19
  st -x, r18
  ret
; @end



#endif