基于C8051F020的DS3231驱动程序

wbymcs51 — Tue, 15 Jul 2008 16:41:48 GMT+08:00

徐丽红王佰营

wbymcs51.blog.bokee.net

;=================================================================

; function: read_ds3231 ;时钟读程序wbymcs51.blog.bokee.net

; input: -------------

; output: second,minute,hour(秒，分，时)

; usage: -------------

;=================================================================

read_ds3231: ;时钟读程序

jb sm_busy, $

setb bHrLw

mov sd_addr, #00h ;ds3231eprom地址

setb sm_busy

setb aa

mov wri_add, #0d0h ;器件地址+写

setb sta

jb sm_busy, $

mov buff, #second

setb sm_busy

setb aa

mov byte_number, #03h ;读数据个数

mov wri_add, #0d1h ;器件地址+读

setb sta

jb sm_busy, $

ret

;=================================================================

; function: write_ds3231 ;时钟写程序wbymcs51.blog.bokee.net

; input: second,minute,hour(秒，分，时)

; output: -------------

; usage: -------------

;=================================================================

write_ds3231: ;时钟写程序

clr bHrLw

mov sd_addr, #00h

mov byte_number,#03h

jb sm_busy, $

setb sm_busy

setb aa

mov wri_add, #0d0h

setb sta

jb sm_busy, $

ret

;====================================================================

; function: Int_smbus I2C总线中断处理程序wbymcs51.blog.bokee.net

; input: -----------------

; output: -----------------

; usage: -----------------

;====================================================================

Int_smbus: ;I2C总线中断处理程序

push psw

push acc

push dph

push dpl

mov psw, #GROUP2

setb si

mov a, smb0sta

anl a, #7fh

cjne a, #00h, isb_08 ;总线错误

setb sto

ljmp smb_end

isb_08: cjne a, #08h, isb_10 ;发送起始数据

;mov smb0dat, #0d0h

mov smb0dat, wri_add

clr sta

ljmp smb_end

isb_10: cjne a, #10h, isb_18 ;重复发送起始位

;mov smb0dat, #0d1h

mov smb0dat, wri_add;read_add

clr sta

ljmp smb_end

isb_18: cjne a, #18h, isb_20 ;发送器件地址+W后收到ACK

mov smb0dat, sd_addr

ljmp smb_end

isb_20: cjne a, #20h, isb_28 ;发送eprom地址+W后收到NACK

setb sto

setb sta

;clr si

ljmp smb_end

isb_28: cjne a, #28h, isb_30 ;发送数据后收到ACK

jnb bHrLw, next1

setb sto

clr sm_busy

sjmp smb_end

next1: mov a, byte_number

cjne a, #00h, isb_not0

setb sto

clr sm_busy

sjmp smb_end

isb_not0:

mov r0, buff

mov smb0dat, @r0

inc buff

dec byte_number

;=====================

; mov a, p4_led

; xrl a, #01h

; mov p4_led, a

;=====================

sjmp smb_end

isb_30: cjne a, #30h, isb_38 ;发送数据后收到NACK

setb sto

setb sta

sjmp smb_end

isb_38: cjne a, #38h, isb_40 ;竞争失败

setb sto

setb sta

sjmp smb_end

isb_40: cjne a, #40h, isb_48 ;发送从地址+R后收到ACK

mov a, byte_number

cjne a, #01h, isb_not1

isb_small1:clr aa

sjmp isb_next

isb_not1:

jc isb_small1

setb aa

isb_next:cjne a, #00h, isb_n0

setb sto

clr sm_busy

isb_n0: sjmp smb_end

isb_48: cjne a, #48h, isb_50 ;发送从地址+R后收到NACK

setb sta

sjmp smb_end

isb_50: cjne a, #50h, isb_58 ;接收数据成功，主机发送ACK

mov a, byte_number

cjne a, #01h, isb_not1a

clr aa

isb_not1a:

isb_n0a:jc small0

mov r0, buff

mov @r0, smb0dat

inc buff

dec byte_number

small0: sjmp smb_end

isb_58: cjne a, #58h, isb_jmp ;发送数据字节后已发送NACK

;mov rec_byte, smb0dat

mov r0, buff

mov @r0, smb0dat

setb sto

clr sm_busy

sjmp smb_end

isb_jmp:setb sto

clr sm_busy

smb_end:

clr si

pop dpl

pop dph

pop acc

pop psw

reti

单片机／开关电源

基于C8051F020的DS3231驱动程序