zxuno-git/utils/rtcst.asm

125 lines
4.5 KiB
NASM

; rtcst.asm - set register and value in pcf8563
; .rtcst VVRR
; -RR register in BCD
; -VV value in BCD
; Copyright (C) 2022 Antonio Villena/McLeod_ideafix
;
; This program is free software: you can redistribute it and/or modify
; it under the terms of the GNU General Public License as published by
; the Free Software Foundation, version 3.
;
; This program is distributed in the hope that it will be useful,
; but WITHOUT ANY WARRANTY; without even the implied warranty of
; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
; GNU General Public License for more details.
;
; You should have received a copy of the GNU General Public License
; along with this program. If not, see <https://www.gnu.org/licenses/>.
;
; Compatible compilers:
; SjAsmPlus, <https://github.com/z00m128/sjasmplus>
; output RTCST
define SCL0SDA0 00b
define SCL0SDA1 01b
define SCL1SDA0 10b
define SCL1SDA1 11b
define I2CADDR_R $a3
define I2CADDR_W $a2
include zxuno.def
include esxdos.def
org $2000 ; comienzo de la ejecución de los comandos ESXDOS
NoPrint ld (Command+1), hl
ld a, h
or l
jp nz, Init
call Print
DateFormat db 13,'Usage:', 13
db ' .RTCST VVRR', 13
db 'VV->Value, RR->Register', 13
ret
Params db 0, 0
Wrong call Print
dz 'Wrong format entered', 13
ret
Init ld b, 5
Repite ld a, (hl)
cp 13
jr z, Fincad
inc hl
dec b
sub $30
cp 16
jr c, Repite
Fincad djnz Wrong
Command ld hl, 0
ld de, Params+2
call ReadBCD
call ReadBCD
ex de, hl
ld e, 2
ld bc, ZXUNOADDR
ld a, i2creg
out (c), a ; selecciono el registro I2C.
inc b
ld a, SCL1SDA1 ;Bus en modo idle.
out (c), a ;Envío condición de START al bus (SDA a 0 mientras mantengo SCL a 1)
dec a ;ld a,SCL1SDA0
out (c), a
ld a, I2CADDR_W ;Envío la dirección I2C de escritura del RTC
call SendByte
LoopSendMess ld a, (hl) ;y en un bucle, me pongo a enviar uno tras otro, los E bytes a los que apunta HL
inc hl
call SendByte
dec e
jr nz, LoopSendMess
call Send0 ;después de enviar el ultimo byte, envío la condición de STOP al bus (envío un 0, con lo que se queda SDA a 0 y SCL a 1, y a continuación pongo SDA a 1)
ld d, SCL1SDA1
out (c), d
or a
ret
SendByte scf ;Enviar un byte por I2C. Byte en A. BC=puerto de datos del ZXUNO ya
adc a, a ;apuntando a I2CREG. Usa y modifica: A, D, flags
Trans call c, Send1
call nc, Send0
add a, a
jr nz, Trans
Send1 ld d, SCL0SDA1
out (c), d
ld d, SCL1SDA1
out (c), d ;Transmito un bit 1 para dejar SDA en modo de alta impedancia y que el receptor puedo ponerlo a 0
ld d, SCL0SDA1
out (c), d
ret ; S flag 0 = ACK received, S flag 1 = ACK not received
Send0 ld d, SCL0SDA0
out (c), d
ld d, SCL1SDA0
out (c), d
ld d, SCL0SDA0
out (c), d
ret
ReadBCD ld a, (hl)
inc hl
sub $30
rlca
rlca
rlca
rlca
ld c, a
ld a, (hl)
inc hl
sub $30
or c
dec de
ld (de), a
ret
include Print.inc