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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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9 b; ~( B) S6 w/ A# L5 k. b% _ #define uchar unsigned char
8 X% @: l8 K3 v5 F #define uint unsigned int
E. r1 P: i8 x3 Y3 _" }+ [5 f V #include <reg52.h>) y0 R+ t2 e1 f& M0 T+ D% v
#include <stdio.h>1 O! ^# w# B7 h8 ?; D
#include <absacc.h>/ k1 F& T% U5 Q0 J7 C4 G/ N
sbit scl=P3^5; //24c02 SCL
5 t/ F9 R* ~1 r( W- z0 k0 |! F1 i sbit sda=P3^4; //24c02 SDA
; C$ k% j* D, q) U. [ sbit DOG=P1^7; //狗8 g% k$ K2 E2 C) l# d, y: b# V
uchar x24c02_read(uchar address); //从24c02的地址address中读取一个字节数据
8 t7 c$ ^- ?+ G' X void x24c02_write(uchar address,uchar info);
; `) ], g* ^* }: ] //向24c02的address地址中写入一字节数据info
9 a7 j* b' P4 d1 e( L! M void x24c02_init(); //24c02初始化子程序4 z, N( B1 ^1 ~" v$ E
void delay1(uchar x);
, N& B+ X6 p# z' ^7 F void flash();
3 U3 @0 W! U2 @- k, ^ void x24c01_init();
* ]) s; R7 n0 K# Q6 L3 T9 p. Z- W void start();' J* E9 r8 W7 X/ a# @+ n7 A
void stop();
) B7 I/ q% y6 ~* \3 \+ C7 r void writex(uchar j);
. c& o6 u& I2 d/ S; w" |* J0 w uchar readx();
1 q, T6 `& u( A. K& H void clock();4 O& L' |- C G8 \
void delay1(uchar x)
5 ` G3 W. {7 y4 p \+ R* } {
; r( `& I( Q% b$ N8 w$ I8 J uint i;
( C: U# U) B9 J1 R4 I) U for(i=0;i<x;i++);
4 x) D/ @9 i$ A4 n! n, F DOG=~DOG;1 \4 A+ n" J% ^9 m1 g
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void flash()
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uchar u;# G4 P+ _: ^! e
DOG=~DOG;5 ]# \5 l2 m0 q5 c
}
& x. J- F5 a1 _( p4 Z void x24c02_init()
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scl=1; flash(); sda=1; flash();
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void start(): E2 k* v C1 I; P
{
, k: k2 ]7 W* Z; N6 P3 ^7 C sda=1; flash(); scl=1; flash(); sda=0; flash(); scl=0; flash();
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2 t6 ^& c! o& j. O* S1 Z6 N; H x6 W void stop()
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sda=0; flash(); scl=1; flash(); sda=1; flash();+ X, S0 o# R# h, B" Y
}
) N& B# J9 X' L6 u0 L( ^' e) [% K E void writex(uchar j)
/ N4 e2 W/ i( u5 f% R {
# N% ?$ @- Y. Y uchar i,temp;
& K& n0 \+ ~/ X3 H. i. P temp=j;
- R4 C4 m1 H* a( g L l for (i=0;i<8;i++){0 _; j+ q7 o( E! Z- S; ^: a
temp=temp<<1; scl=0; flash(); sda=CY; flash(); scl=1; 6 @1 E+ K. k1 J( r* i+ L' Y
flash();( ^% z+ E& m p$ x4 }: W7 a! O
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scl=0; flash(); sda=1; flash();6 I+ W. T y1 @; t9 X" A/ d
}
0 `1 p& |4 B4 V7 V1 h uchar readx()
; F- N0 ^& \4 ], n {
' B" ]: g, ^5 f/ Y$ G" \3 N2 d) ` uchar i,j,k=0;6 G7 _! c3 e5 c: _" n# I; }
scl=0; flash(); sda=1;
C. a6 x( {6 ]; N2 r for (i=0;i<8;i++){! v7 j$ A3 Y: ~' S" Z
flash(); scl=1; flash();, D7 Y1 v7 r6 R- a/ R$ B0 Z
if (sda==1) j=1;
! R+ z! g6 p+ H else j=0;8 x& z2 V( H. y' l7 \: O4 }
k=(k<<1)|j; scl=0;% t4 E% I( p; p8 K; c
}
! l& |# G7 I& c8 O$ G% D' ] flash(); return(k);: z- S6 f' V$ h8 l
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void clock()
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uchar i=0;9 `& T4 q) W/ r# W
scl=1; flash();
5 U0 y3 o) Z- z3 N! W4 p. w while ((sda==1)&&(i<255))i++;% e4 Z0 H: s! ?( m( L5 j* r
scl=0; flash();, ~5 z: ^/ N1 n5 b& s9 l
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uchar x24c02_read(uchar address) @; k% K5 q" m( h. W9 u, @/ Q
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uchar i;
8 t3 u! L9 E$ V1 N; h start(); writex(0xa0);
6 G: g% E4 R! A9 q# ^9 Z: I* y# o3 h# C clock(); writex(address);7 x( ~* ~( `+ d( F ]; i2 r' L
clock(); start();
1 k; r+ @2 O9 X& Q writex(0xa1); clock();9 G7 @! a/ _/ Q& _ @0 ]
i=readx(); stop();
; v$ x2 W0 U* e$ p% I( K delay1(10);6 y8 k' f' z9 `. b3 E$ w& R9 N2 ~
return(i);
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! w1 u0 k9 h7 |' m! P void x24c02_write(uchar address,uchar info)$ ]. N; n" s# }/ p
{
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start(); writex(0xa0);
0 V+ O% P" \4 _9 T( y clock(); writex(address);; L W# p/ R0 ?) n
clock(); writex(info);8 ~5 b% P6 U$ Y$ v3 Q) }, P! C
clock(); stop();
# d; G. \4 I6 V' c0 { EA=1;: a/ l# b6 P# C4 h
delay1(50);% K0 s1 ^8 o+ S* z/ `
} |
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