Files
aqhomecontrol/avr/modules/uart_fd/macros.asm
2025-08-25 10:24:48 +02:00

232 lines
6.2 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. *
; ***************************************************************************
#ifndef AVR_MODULES_UARTFD_MACROS_ASM
#define AVR_MODULES_UARTFD_MACROS_ASM
.macro M_UARTFD_SET_CHARFORMAT
ldi r16, (1<<UCSZ@01) | (1<<UCSZ@00) ; 1 stop bit, 8 databits
outr UCSR@0C, r16
.endmacro
.macro M_UARTFD_SET_BAUDRATE
.if clock == 8000000
ldi r16, 25 ; (19.2Kb/s at 8MHz)
ldi r17, 0
.elif clock == 1000000
ldi r16, 2 ; (19.2Kb/s at 1MHz)
ldi r17, 0
.else
.error "Unhandled clock frequency"
.endif
outr UBRR@0H, r17
outr UBRR@0L, r16
.endmacro
.macro M_UARTFD_START_RX
inr r16, UCSR@0B
sbr r16, (1<<RXCIE@0) | (1<<RXEN@0) ; enable RX complete interrupt, enable receive
outr UCSR@0B, r16
.endmacro
.macro M_UARTFD_STOP_RX
inr r16, UCSR@0B
cbr r16, (1<<RXCIE@0) | (1<<RXEN@0) ; disable RX complete interrupt, disable receive
outr UCSR@0B, r16
.endmacro
.macro M_UARTFD_START_TX
inr r16, UCSR@0A
cbr r16, (1<<TXC@0) ; clear TXCn interrupt
outr UCSR@0A, r16
inr r16, UCSR@0B
; sbr r16, (1<<UDRIE@0) | (1<<TXCIE@0) | (1<<TXEN@0) ; enable TX UDRE and TXC interrupt, enable transceive
sbr r16, (1<<UDRIE@0) | (1<<TXEN@0) ; enable TX UDRE interrupt, enable transceive
outr UCSR@0B, r16
.endmacro
.macro M_UARTFD_STOP_TX
inr r16, UCSR@0B
cbr r16, (1<<UDRIE@0) | (1<<TXCIE@0) | (1<<TXEN@0) ; disable TX UDRE and TXC interrupt, disable transceive
outr UCSR@0B, r16
.endmacro
.macro M_UARTFD_STOP_TXIRQS
inr r16, UCSR@0B
cbr r16, (1<<UDRIE@0) | (1<<TXCIE@0) ; disable TX UDRE and TXC interrupt
outr UCSR@0B, r16
.endmacro
.macro M_UARTFD_FLUSH_IN
l_loop_%:
inr r16, UCSR@0A
sbrs r16, RXC@0
rjmp l_end_% ; no data
inr r16, UDR@0 ; r16=received char
rjmp l_loop_%
l_end_%:
.endmacro
; @end
; ---------------------------------------------------------------------------
; @macro M_UARTFD_RXCHAR_ISR
;
; @clobbers r16, r17, X
.macro M_UARTFD_RXCHAR_ISR
ldd r16, Y+UARTFD_IFACE_OFFS_STATUS
andi r16, (1<<UARTFD_IFACE_STATUS_BIT_SKIPPING)
breq l_readNext_%
; skipping mode, just skip character
inr r16, UDR@0 ; r16=received char
rjmp l_resetReadTimer_% ; skipping
l_readNext_%:
inr r16, UCSR@0A ; check for errors
andi r16, (1<<FE@0) | (1<<DOR@0) | (1<<UPE@0)
brne l_hwerr_%
inr r16, UCSR@0A
sbrs r16, RXC@0
rjmp l_end_% ; no data
inr r16, UDR@0 ; r16=received char
ldd r17, Y+UARTFD_IFACE_OFFS_RBUFLEFT
tst r17
breq l_overrun_%
dec r17
std Y+UARTFD_IFACE_OFFS_RBUFLEFT, r17
ldd r17, Y+UARTFD_IFACE_OFFS_RBUFUSED
inc r17
std Y+UARTFD_IFACE_OFFS_RBUFUSED, r17
ldd xl, Y+UARTFD_IFACE_OFFS_RPOS_LOW
ldd xh, Y+UARTFD_IFACE_OFFS_RPOS_HIGH
st X+, r16
std Y+UARTFD_IFACE_OFFS_RPOS_LOW, xl
std Y+UARTFD_IFACE_OFFS_RPOS_HIGH, xh
cpi r17, 2 ; exactly 2 bytes in buffer?
brne l_resetReadTimer_%
; determine message size
inc r16 ; last byte was payload length, add byte for crc
ldd r17, Y+UARTFD_IFACE_OFFS_RBUFLEFT
cp r17, r16 ; compare remaining length against remaining space
brcs l_badMsgSize_%
std Y+UARTFD_IFACE_OFFS_RBUFLEFT, r16
l_resetReadTimer_%:
clr r16
std Y+NET_IFACE_OFFS_READTIMER, r16 ; reset read timer
rjmp l_end_%
l_hwerr_%:
ldd r16, Y+UARTFD_IFACE_OFFS_STATUS
ori r16, (1<<UARTFD_IFACE_STATUS_BIT_HWERR) | (1<<UARTFD_IFACE_STATUS_BIT_SKIPPING)
std Y+UARTFD_IFACE_OFFS_STATUS, r16
rjmp l_end_%
l_badMsgSize_%:
ldd r16, Y+UARTFD_IFACE_OFFS_STATUS
ori r16, (1<<UARTFD_IFACE_STATUS_BIT_BADMSGSIZE) | (1<<UARTFD_IFACE_STATUS_BIT_SKIPPING)
std Y+UARTFD_IFACE_OFFS_STATUS, r16
rjmp l_end_%
l_overrun_%:
ldd r16, Y+UARTFD_IFACE_OFFS_STATUS
ori r16, (1<<UARTFD_IFACE_STATUS_BIT_OVERRUN) | (1<<UARTFD_IFACE_STATUS_BIT_SKIPPING)
std Y+UARTFD_IFACE_OFFS_STATUS, r16
l_end_%:
.endmacro
; @end
; ---------------------------------------------------------------------------
; @macro M_UARTFD_TXUDRE_ISR
;
; @clobbers R16, R17, X
.macro M_UARTFD_TXUDRE_ISR
lds r16, UCSR@0A ; check for UDRE flag
sbrs r16,UDRE@0
rjmp l_disable_irq_% ; not ready
; check whether we have an active write buffer
ldd r16, Y+UARTFD_IFACE_OFFS_WBUFNUM
cpi r16, 0xff
breq l_disable_irq_% ; no buffer
; check whether there is data in the buffer to send
ldd r17, Y+UARTFD_IFACE_OFFS_WBUFLEFT ; r17=bytes left
tst r17
breq l_disable_irq_% ; nothing left to write
; get read ptr, read byte, inc read ptr, store ptr and bytesLeft
ldd xl, Y+UARTFD_IFACE_OFFS_WPOS_LOW
ldd xh, Y+UARTFD_IFACE_OFFS_WPOS_HIGH
ld r16, X+ ; r16=byte to write
std Y+UARTFD_IFACE_OFFS_WPOS_LOW, xl
std Y+UARTFD_IFACE_OFFS_WPOS_HIGH, xh
dec r17
std Y+UARTFD_IFACE_OFFS_WBUFLEFT, r17
; send byte, reset write timer
sts UDR@0, r16
clr r16
std Y+NET_IFACE_OFFS_WRITETIMER, r16 ; reset write timer
; still bytes left to write?
tst r17
brne l_end_%
l_disable_irq_%:
; disable further UDRE interrupts
lds r16, UCSR@0B
cbr r16, (1<<UDRIE@0) ; disable TX data register empty interrupt
sts UCSR@0B, r16
l_end_%:
.endmacro
; @end
; ---------------------------------------------------------------------------
; @macro M_UARTFD_TXCHAR_ISR
;
; @clobbers R16, R17, X
.macro M_UARTFD_TXCHAR_ISR
; disable further TXC interrupts
inr r16, UCSR@0B
cbr r16, (1<<TXC@0) ; disable TXC interrupt
outr UCSR@0B, r16
.endmacro
; @end
#endif