; ***************************************************************************
; 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.   *
; ***************************************************************************


.equ RINGBUFFERY_OFFS_MAXSIZE  = 0
.equ RINGBUFFERY_OFFS_USED     = 1
.equ RINGBUFFERY_OFFS_READPOS  = 2
.equ RINGBUFFERY_OFFS_WRITEPOS = 3
.equ RINGBUFFERY_OFFS_DATA     = 4



; ---------------------------------------------------------------------------
; @routine RingBufferY_Init
;
; @param R16 size of ringbuffer
; @param Y   base address of ringbuffer struct
; @return CFLAG set if okay, cleared on error (i.e. buffer full)
; @clobbers R17

RingBufferY_Init:
  std Y+RINGBUFFERY_OFFS_MAXSIZE, r16
  rjmp RingBufferY_Reset
; @end



; ---------------------------------------------------------------------------
; @routine RingBufferY_WriteByte
;
; @param R16 byte to write
; @param Y   base address of ringbuffer struct
; @return CFLAG set if okay, cleared on error (i.e. buffer full)
; @clobbers R17, R18, X

RingBufferY_WriteByte:
  m_ringbuffer_y_writebyte \
    RINGBUFFERY_OFFS_MAXSIZE, \
    RINGBUFFERY_OFFS_USED, \
    RINGBUFFERY_OFFS_READPOS, \
    RINGBUFFERY_OFFS_WRITEPOS, \
    RINGBUFFERY_OFFS_DATA
  ret
; @end



; ---------------------------------------------------------------------------
; @macro m_ringbuffer_y_readbyte
;
; @param Y   base address of ringbuffer struct
; @return CFLAG set if okay, cleared on error (i.e. buffer empty)
; @return R16 byte read
; @clobbers R17, R18, X

RingBufferY_ReadByte:
  m_ringbuffer_y_readbyte \
    RINGBUFFERY_OFFS_MAXSIZE, \
    RINGBUFFERY_OFFS_USED, \
    RINGBUFFERY_OFFS_READPOS, \
    RINGBUFFERY_OFFS_WRITEPOS, \
    RINGBUFFERY_OFFS_DATA
  ret
; @end



; ---------------------------------------------------------------------------
; @macro m_ringbuffer_y_reset
;
; @param Y   base address of ringbuffer struct
; @clobbers R17

RingBufferY_Reset:
  m_ringbuffer_y_reset \
    RINGBUFFERY_OFFS_MAXSIZE, \
    RINGBUFFERY_OFFS_USED, \
    RINGBUFFERY_OFFS_READPOS, \
    RINGBUFFERY_OFFS_WRITEPOS, \
    RINGBUFFERY_OFFS_DATA
  ret
; @end