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|
;--------------------------------------------------------
; File Created by SDCC : free open source ANSI-C Compiler
; Version 3.6.0 #9615 (Linux)
;--------------------------------------------------------
.module usart
.optsdcc -mz80
;--------------------------------------------------------
; Public variables in this module
;--------------------------------------------------------
.globl _usart_word_length
.globl _usart_set_baudrate
.globl _usart_set_parity
.globl _usart_set_stop_bits
.globl _usart_set_autoflow
.globl _usart_init
.globl _usart_transmit
.globl _usart_receive
.globl _usart_write
.globl _usart_read
;--------------------------------------------------------
; special function registers
;--------------------------------------------------------
;--------------------------------------------------------
; ram data
;--------------------------------------------------------
.area _DATA
;--------------------------------------------------------
; ram data
;--------------------------------------------------------
.area _INITIALIZED
__usart:
.ds 2
;--------------------------------------------------------
; absolute external ram data
;--------------------------------------------------------
.area _DABS (ABS)
;--------------------------------------------------------
; global & static initialisations
;--------------------------------------------------------
.area _HOME
.area _GSINIT
.area _GSFINAL
.area _GSINIT
;--------------------------------------------------------
; Home
;--------------------------------------------------------
.area _HOME
.area _HOME
;--------------------------------------------------------
; code
;--------------------------------------------------------
.area _CODE
;usart.c:5: void usart_set_baudrate(uint16_t baudrate)
; ---------------------------------
; Function usart_set_baudrate
; ---------------------------------
_usart_set_baudrate::
push ix
ld ix,#0
add ix,sp
;usart.c:8: _usart->LCR.divisor_latch_access = 1;
ld hl,(__usart)
ld bc,#0x0004
add hl,bc
ld a,(hl)
or a,#0x80
ld (hl),a
;usart.c:9: _usart->buffer = 0x00FF & baudrate; // LSBs
ld hl,(__usart)
ld c,4 (ix)
ld (hl),c
;usart.c:10: memcpy(&_usart->IER, &(baudrate >>8), 1);
ld de,(__usart)
inc de
ld l,5 (ix)
ld h,#0x00
ld a, (hl)
ld (de), a
;usart.c:12: _usart->LCR.divisor_latch_access = 0;
ld hl,(__usart)
ld bc,#0x0004
add hl,bc
ld a,(hl)
and a,#0x7f
ld (hl),a
pop ix
ret
;usart.c:15: void usart_set_parity(int mode)
; ---------------------------------
; Function usart_set_parity
; ---------------------------------
_usart_set_parity::
;usart.c:18: _usart->LCR.even_parity = 1;
ld hl,(__usart)
ld bc,#0x0004
add hl,bc
;usart.c:17: if (mode == USART_PARITY_EVEN) {
ld iy,#2
add iy,sp
ld a,0 (iy)
dec a
jr NZ,00104$
ld a,1 (iy)
or a, a
jr NZ,00104$
;usart.c:18: _usart->LCR.even_parity = 1;
ld a,(hl)
or a,#0x10
ld (hl),a
jr 00105$
00104$:
;usart.c:20: else if (mode == USART_PARITY_ODD) {
ld iy,#2
add iy,sp
ld a,0 (iy)
sub a, #0x02
jr NZ,00105$
ld a,1 (iy)
or a, a
jr NZ,00105$
;usart.c:21: _usart->LCR.even_parity = 0;
ld a,(hl)
and a,#0xef
ld (hl),a
00105$:
;usart.c:24: _usart->LCR.parity = (mode == USART_PARITY_NONE) ? 0 : 1;
ld hl,(__usart)
ld bc,#0x0004
add hl,bc
ld iy,#2
add iy,sp
ld a,0 (iy)
rlca
rlca
rlca
and a,#0xf8
and a,#0x08
ld c,a
ld a,(hl)
and a,#0xf7
or a,c
ld (hl),a
ret
;usart.c:27: void usart_set_stop_bits(int count)
; ---------------------------------
; Function usart_set_stop_bits
; ---------------------------------
_usart_set_stop_bits::
;usart.c:29: _usart->LCR.stop_bits = (count == USART_STOP_BITS_1) ? 0 : 1;
ld bc,(__usart)
inc bc
inc bc
inc bc
inc bc
ld iy,#2
add iy,sp
ld a,0 (iy)
sub a, #0x0a
jr NZ,00103$
ld a,1 (iy)
or a, a
jr NZ,00103$
ld a,#0x01
jr 00104$
00103$:
xor a,a
00104$:
xor a, #0x01
add a, a
add a, a
and a,#0x04
ld l,a
ld a,(bc)
and a,#0xfb
or a,l
ld (bc),a
ret
;usart.c:32: void usart_word_length(int length)
; ---------------------------------
; Function usart_word_length
; ---------------------------------
_usart_word_length::
;usart.c:34: _usart->LCR.word_length = length;
ld hl,(__usart)
ld bc,#0x0004
add hl,bc
ld iy,#2
add iy,sp
ld a,0 (iy)
and a,#0x03
ld c,a
ld a,(hl)
and a,#0xfc
or a,c
ld (hl),a
ret
;usart.c:37: void usart_set_autoflow(int mode)
; ---------------------------------
; Function usart_set_autoflow
; ---------------------------------
_usart_set_autoflow::
;usart.c:39: _usart->MCR.autoflow = (mode == USART_AUTOFLOW_OFF) ? 0 : 1;
ld hl,(__usart)
ld bc,#0x000c
add hl,bc
ld iy,#2
add iy,sp
ld a,0 (iy)
and a,#0x01
ld c,a
ld a,(hl)
and a,#0xfe
or a,c
ld (hl),a
;usart.c:40: _usart->MCR.data_terminal_ready = (mode == USART_AUTOFLOW_ALL);
ld hl,(__usart)
ld bc,#0x0005
add hl,bc
ld a,0 (iy)
sub a, #0x03
jr NZ,00103$
ld a,1 (iy)
or a, a
jr NZ,00103$
ld a,#0x01
jr 00104$
00103$:
xor a,a
00104$:
and a,#0x01
ld c,a
ld a,(hl)
and a,#0xfe
or a,c
ld (hl),a
ret
;usart.c:43: inline void usart_init(uint16_t baudrate, int parity, int stop_bits)
; ---------------------------------
; Function usart_init
; ---------------------------------
_usart_init::
;usart.c:45: usart_set_baudrate(baudrate);
pop bc
pop hl
push hl
push bc
push hl
call _usart_set_baudrate
pop af
;usart.c:46: usart_set_parity(parity);
ld hl, #4
add hl, sp
ld c, (hl)
inc hl
ld b, (hl)
push bc
call _usart_set_parity
pop af
;usart.c:47: usart_set_stop_bits(stop_bits);
ld hl, #6
add hl, sp
ld c, (hl)
inc hl
ld b, (hl)
push bc
call _usart_set_stop_bits
;usart.c:48: usart_set_autoflow(USART_AUTOFLOW_OFF);
ld hl, #0x0000
ex (sp),hl
call _usart_set_autoflow
pop af
ret
;usart.c:51: void usart_transmit(uint8_t data)
; ---------------------------------
; Function usart_transmit
; ---------------------------------
_usart_transmit::
;usart.c:53: _usart->buffer = data;
ld hl,(__usart)
ld iy,#2
add iy,sp
ld a,0 (iy)
ld (hl),a
;usart.c:54: while (_usart->LSR.transmitter_holder_empty == 0); // wait
00101$:
ld hl,(__usart)
ld bc,#0x000d
add hl,bc
ld a,(hl)
rlca
rlca
rlca
jr NC,00101$
ret
;usart.c:57: uint8_t usart_receive()
; ---------------------------------
; Function usart_receive
; ---------------------------------
_usart_receive::
;usart.c:59: return _usart->buffer;
ld hl,(__usart)
ld l,(hl)
ret
;usart.c:62: int usart_write(uint8_t *data, size_t size)
; ---------------------------------
; Function usart_write
; ---------------------------------
_usart_write::
push ix
ld ix,#0
add ix,sp
push af
;usart.c:64: uint8_t *dp = data;
ld a,4 (ix)
ld -2 (ix),a
ld a,5 (ix)
ld -1 (ix),a
;usart.c:66: while (size--) {
ld c,6 (ix)
ld b,7 (ix)
00104$:
ld e, c
ld d, b
dec bc
ld a,d
or a,e
jr Z,00106$
;usart.c:67: _usart->buffer = *(dp++);
ld de,(__usart)
pop hl
push hl
ld a,(hl)
inc -2 (ix)
jr NZ,00126$
inc -1 (ix)
00126$:
ld (de),a
;usart.c:68: while (_usart->LSR.transmitter_empty);
00101$:
ld hl,(__usart)
ld de,#0x000d
add hl,de
ld a,(hl)
rlca
rlca
jr NC,00104$
jr 00101$
00106$:
;usart.c:72: return size;
ld l, c
ld h, b
ld sp, ix
pop ix
ret
;usart.c:75: int usart_read(uint8_t *buffer, size_t count)
; ---------------------------------
; Function usart_read
; ---------------------------------
_usart_read::
push ix
ld ix,#0
add ix,sp
ld hl,#-6
add hl,sp
ld sp,hl
;usart.c:77: uint8_t *bp = buffer;
ld a,4 (ix)
ld -4 (ix),a
ld a,5 (ix)
ld -3 (ix),a
;usart.c:80: while (count--) {
ld c,6 (ix)
ld b,7 (ix)
ld hl,#0x0000
ex (sp), hl
00105$:
ld e, c
ld d, b
dec bc
ld a,d
or a,e
jr Z,00107$
;usart.c:81: *(bp++) = _usart->buffer;
ld hl,(__usart)
ld e,(hl)
ld l,-4 (ix)
ld h,-3 (ix)
ld (hl),e
inc -4 (ix)
jr NZ,00123$
inc -3 (ix)
00123$:
ld de,(__usart)
;usart.c:83: if (_usart->LSR.framing_error || _usart->LSR.parity_error) {
ld hl,#0x000d
add hl,de
ld -2 (ix),l
ld -1 (ix),h
ld l,-2 (ix)
ld h,-1 (ix)
ld a,(hl)
rrca
rrca
rrca
and a,#0x01
jr NZ,00101$
ld l,-2 (ix)
ld h,-1 (ix)
ld a,(hl)
rrca
rrca
and a,#0x01
jr Z,00102$
00101$:
;usart.c:84: bp--; // delete last byte (?)
ld l,-4 (ix)
ld h,-3 (ix)
dec hl
ld -4 (ix),l
ld -3 (ix),h
jr 00105$
00102$:
;usart.c:86: read_count++;
inc -6 (ix)
jr NZ,00105$
inc -5 (ix)
jr 00105$
00107$:
;usart.c:90: return read_count;
pop hl
push hl
ld sp, ix
pop ix
ret
.area _CODE
.area _INITIALIZER
__xinit___usart:
.dw #0x4000
.area _CABS (ABS)
|
