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发表于 2008-8-1 16:09:00
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来自: 中国河南新乡
就是啊,首先你要看懂I2C协议,在就是根据某个芯片,看一下控制程序就大概可以了!下面就是24C02的读写程序:
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0 B4 @5 t2 o1 Y- k #define uchar unsigned char
. k" D& \3 q& ]- r8 A( t. x/ O# D #define uint unsigned int
' o5 C5 T1 Z- ?% |) g: h #include <reg52.h>
) \' j2 j! l% o9 E, ]! ~: N #include <stdio.h> z; ^ q: ?; `$ n$ e
#include <absacc.h>
' Z! v3 [3 b$ q/ x+ l& ? sbit scl=P3^5; //24c02 SCL! I- N8 S1 ]. f
sbit sda=P3^4; //24c02 SDA( C) K2 e: U; o6 E& r$ |0 o
sbit DOG=P1^7; //狗
% C* N% a$ E' x/ A1 h uchar x24c02_read(uchar address); //从24c02的地址address中读取一个字节数据3 O% H7 |7 i- _1 ?
void x24c02_write(uchar address,uchar info);
8 O1 t. z9 r K8 R* a; M8 S K //向24c02的address地址中写入一字节数据info
+ Y9 D1 g+ S2 Z$ Y7 ?( t8 Z$ e void x24c02_init(); //24c02初始化子程序# Y( _7 n& H8 T0 R: E% j
void delay1(uchar x);* r9 x) R5 F1 y @* v% r7 ~* x
void flash();5 a: i" I: f, y9 n- k9 a& t
void x24c01_init();
& A) X0 P! J9 D* i1 M8 g6 S void start();: j) E4 B7 t# |/ ]( S/ K
void stop();
# `0 f8 J# X" u& t$ P void writex(uchar j);0 \% O( F! u* P4 ?: {
uchar readx();" J1 J$ P8 D7 k- j! D
void clock();
4 Q! O$ q* C( @% s& L8 C0 M, i6 A void delay1(uchar x)
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uint i;
3 f* w3 U" E4 {7 \ for(i=0;i<x;i++);
- \% X n9 n. P& v( K% p DOG=~DOG;
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z3 z* r W) ~# N void flash()
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uchar u;2 Y) }+ W1 B9 k% N" |
DOG=~DOG;
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void x24c02_init()" F: l$ S. N4 b3 v7 b
{
, x! `* w2 `7 O! f; c; Y scl=1; flash(); sda=1; flash();
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void start(): P0 V$ }' G' n% Q' d4 p
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sda=1; flash(); scl=1; flash(); sda=0; flash(); scl=0; flash();
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) t3 G6 J8 e8 `9 r void stop()* Z K, o% y: z$ T
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sda=0; flash(); scl=1; flash(); sda=1; flash();6 [# K/ g/ \& x( i3 @ L, J
}
" f) a8 \2 @* D3 e void writex(uchar j)
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/ D1 }* ^& T$ Y" ~ uchar i,temp;/ @4 `4 o7 X: ?, a* z0 C/ @2 {. w$ h% ?
temp=j;
, _8 d7 y7 z1 a6 |0 h; K for (i=0;i<8;i++){! q8 j+ _- _# ?- R
temp=temp<<1; scl=0; flash(); sda=CY; flash(); scl=1;
, b5 z; [9 v2 G- Z flash();
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scl=0; flash(); sda=1; flash();
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! ]8 }2 i- q+ a% Q uchar readx()# X" M& D$ O2 [( Z8 `
{
- A& O9 C \4 |& r; l7 T uchar i,j,k=0;
! Q+ b6 }- S' }2 j$ x' A scl=0; flash(); sda=1;% {) ?2 {5 U+ d% }' ?2 e
for (i=0;i<8;i++){! o% [. y/ N2 y, C r, u
flash(); scl=1; flash();2 R6 o- ]- h( j- e% H" q- R e
if (sda==1) j=1;' V- M9 K. N1 y' ]1 d6 G
else j=0;
0 f# d2 Z% X% R; _ k=(k<<1)|j; scl=0;
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: ] j3 [/ M6 X. E; z5 c flash(); return(k); |3 B1 h! a* A% f# `/ a9 H
}
' U3 V7 M% a! h; F2 m. d) D4 W void clock()
7 S% h9 R3 G" Q( L, ~ {
9 U3 S# B2 e. o6 m) L0 t% B8 B uchar i=0;% N) R' M& C( K7 R# }5 V
scl=1; flash();
2 D% V# u7 v. s4 v while ((sda==1)&&(i<255))i++;3 Z1 d9 W' e+ A# c* m2 ?
scl=0; flash();
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' u+ f# E' t2 h0 G Y3 Q uchar x24c02_read(uchar address)2 S5 V6 {0 b4 x! c7 k& C
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uchar i;7 ?( U! A: B% P K! t% P
start(); writex(0xa0);
& f6 S; F* M3 L% ~9 j5 q0 Y clock(); writex(address);
$ f! e! P) d1 r- @ clock(); start();
- k5 ^# R9 b" |1 F* H writex(0xa1); clock();
7 U6 @/ @- ]6 ?) ]$ ~( P& ] i=readx(); stop();6 J4 J# J/ }% o
delay1(10);! P% M1 I. m" [# b
return(i);
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' U3 @+ o1 A7 d/ U3 N5 b E' l void x24c02_write(uchar address,uchar info)
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4 F2 U$ e# E% N7 H* J EA=0;
; K* c5 I7 u" ^* |% V start(); writex(0xa0);, d# x- a( o; u* M1 U9 U4 Y+ Z2 r
clock(); writex(address);
' \4 O/ R; a8 c+ t7 n; T6 t8 B clock(); writex(info);) L! \$ D, [/ r
clock(); stop();; r2 U" a7 H, S# H& v- H
EA=1;6 w1 |9 u9 J% i) W+ B; S' Z) b, x
delay1(50);; D. `5 U. n, ^8 h( [
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