Files
aqhomecontrol/avr/modules/uart_hw/lowlevel.asm
2025-02-11 01:13:00 +01:00

124 lines
3.2 KiB
NASM

; ***************************************************************************
; 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. *
; ***************************************************************************
.cseg
; ---------------------------------------------------------------------------
; @routine UART_HW_Init @global
;
; Initializes buffers.
;
; @clobbers R16, R17, X, Y
UART_HW_Init:
ldi xh, HIGH(uartHwDataBegin)
ldi xl, LOW(uartHwDataBegin)
clr r16
ldi r17, (uartHwDataEnd-uartHwDataBegin)
rcall Utils_FillSram
rcall UART_HW_FixedBuffers_Init
ldi r16, UART_HW_MSGNUMINBUF_SIZE
ldi yl, LOW(uartHw_ringBufferMsgNumIn)
ldi yh, HIGH(uartHw_ringBufferMsgNumIn)
rcall RingBufferY_Init
ldi r16, UART_HW_MSGNUMOUTBUF_SIZE
ldi yl, LOW(uartHw_ringBufferMsgNumOut)
ldi yh, HIGH(uartHw_ringBufferMsgNumOut)
rcall RingBufferY_Init
sec
ret
; @end
; ---------------------------------------------------------------------------
; @routine UART_HW_InterfaceInit @global
;
; @param Y pointer to interface data in SRAM (see @ref UART_HW_IFACE_OFFS_STATE)
; @clobbers R16, R17, X
UART_HW_InterfaceInit:
mov xl, yl
mov xh, yh
ldi r17, UART_HW_IFACE_SIZE
clr r16
rcall Utils_FillSram ; (R17, X)
ldi r16, 0xff
std Y+UART_HW_IFACE_OFFS_READBUFNUM, r16
std Y+UART_HW_IFACE_OFFS_WRITEBUFNUM, r16
ldi r16, UART_HW_READMODE_OFF
std Y+UART_HW_IFACE_OFFS_READMODE, r16
ldi r16, UART_HW_WRITEMODE_IDLE
std Y+UART_HW_IFACE_OFFS_WRITEMODE, r16
ret
; @end
; ---------------------------------------------------------------------------
; @routine UART_HW_Interface_SetReadBuffer @global
;
; @param Y pointer to interface data in SRAM (see @ref UART_HW_IFACE_OFFS_STATE)
; @param r16 read buffer number
; @param X read buffer pos
; @clobbers R17
UART_HW_Interface_SetReadBuffer:
std Y+UART_HW_IFACE_OFFS_READBUFNUM, r16
adiw xh:xl, 1
std Y+UART_HW_IFACE_OFFS_READBUFPOSLOW, xl
std Y+UART_HW_IFACE_OFFS_READBUFPOSHIGH, xh
sbiw xh:xl, 1
clr r17
std Y+UART_HW_IFACE_OFFS_READBUFUSED, r17
std Y+UART_HW_IFACE_OFFS_READBUFLEFT, r17
ret
; @end
; ---------------------------------------------------------------------------
; @routine UART_HW_Interface_SetWriteBuffer @global
;
; @param Y pointer to interface data in SRAM (see @ref UART_HW_IFACE_OFFS_STATE)
; @param r16 write buffer number
; @param X write buffer pos
; @clobbers r17
UART_HW_Interface_SetWriteBuffer:
std Y+UART_HW_IFACE_OFFS_WRITEBUFNUM, r16
adiw xh:xl, 1
std Y+UART_HW_IFACE_OFFS_WRITEBUFPOSLOW, xl ; begin of msg (dest addr byte)
std Y+UART_HW_IFACE_OFFS_WRITEBUFPOSHIGH, xh
adiw xh:xl, 1
ld r17, X ; payload length byte
sbiw xh:xl, 2 ; back to start of buffer
inc r17
inc r17
inc r17
std Y+UART_HW_IFACE_OFFS_WRITEBUFUSED, r17
std Y+UART_HW_IFACE_OFFS_WRITEBUFLEFT, r17
ret
; @end