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发表于 2008-8-1 16:09:00
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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:" w2 p, F X. r8 O9 @
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#define uchar unsigned char
! h( N( ]9 B- i #define uint unsigned int
+ r$ [9 R: ?. U #include <reg52.h>
# u, S9 E' q) r; E1 g #include <stdio.h>
% l4 U" _1 z" ?! H& `) K/ J #include <absacc.h>
" [- P2 r6 ?6 O. |6 N sbit scl=P3^5; //24c02 SCL
+ P( Z+ `& P, e* D3 A( Y! L: E sbit sda=P3^4; //24c02 SDA
/ E! W W0 r2 k8 y8 T" l sbit DOG=P1^7; //狗
' u" \8 X. s& w4 S0 r7 B4 C uchar x24c02_read(uchar address); //从24c02的地址address中读取一个字节数据
: u6 \; e' Q( Y* J4 j void x24c02_write(uchar address,uchar info);
- `/ s( U2 ~, l$ d& C //向24c02的address地址中写入一字节数据info
0 J6 D: l( X5 L void x24c02_init(); //24c02初始化子程序
! \3 x- S/ i' r5 ]0 ~ void delay1(uchar x);
, H) d V4 ]0 E0 T" g, n. y) d) g X void flash();1 }+ P! e+ D; g1 N, W5 e+ a
void x24c01_init();: ?) |7 h |2 G2 s5 I
void start();+ g( o8 d- \+ o! n G) W
void stop(); h% G+ ]6 S3 ^# t# K0 O0 a
void writex(uchar j);
& n% r t5 y# Q7 v) M uchar readx();; y% }1 M. B u& o# w
void clock();+ n- C) ~ e* }5 j$ d# E' R1 _5 `
void delay1(uchar x)
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uint i;
3 a4 B' K1 K& A& h% o for(i=0;i<x;i++);
- ?( ~ c" S3 c* A8 U# e' _( w DOG=~DOG;
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, c& j* a; p. g" Q- m6 x! h5 u2 I9 k void flash()* s5 D/ M6 V- X& I$ ?' l. D
{
! o6 G t0 `2 w* d7 O% l, c uchar u;
% K' [, c, X2 O* B2 e0 R9 G DOG=~DOG;
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/ ^, F& _1 _& r$ @, ?- G2 ` void x24c02_init()
% B: n0 ^/ U1 J. k+ K% q {
2 n! [ p& B1 R( S5 N scl=1; flash(); sda=1; flash();
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+ m( o$ c( ^" d void start()0 X& u& \) n5 e3 n( p0 G `! k
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sda=1; flash(); scl=1; flash(); sda=0; flash(); scl=0; flash();1 a2 C" K7 e+ q3 q3 T
}
$ f. a$ J+ v7 h2 D5 ^4 P void stop()
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sda=0; flash(); scl=1; flash(); sda=1; flash();
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void writex(uchar j) Q8 ~5 e4 h8 ?* T6 {
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uchar i,temp;
; ?0 n9 {; F5 a temp=j;* @0 }4 H5 n: D2 {
for (i=0;i<8;i++){
& d; U2 V- X/ Q* v8 v9 w- X temp=temp<<1; scl=0; flash(); sda=CY; flash(); scl=1;
' ]) I2 a. K; q5 d flash();
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; P3 }% c& t, C: f$ C! q6 r scl=0; flash(); sda=1; flash();6 N: d- N( _- q4 o( g$ G1 } a
}; P/ x1 f) `! M: h
uchar readx()% q! m% I6 u( l8 L. k
{
* {" E% N$ l& j R uchar i,j,k=0;$ L( \ c, R0 G% l& @* Z
scl=0; flash(); sda=1;
$ z" A% F5 D3 f5 _; ]' x/ Y for (i=0;i<8;i++){3 }, Q! r5 F3 B/ L! ~5 e3 Y
flash(); scl=1; flash();
$ O* n5 j$ U. z* s* ^$ m/ K if (sda==1) j=1;" u# Q( A& q( ^6 Y# Y# p
else j=0;$ ~: Y- P. B' C9 ^7 s
k=(k<<1)|j; scl=0;
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! S- ^# ^1 ?: d" }! y flash(); return(k);
/ y7 W/ @# U0 f3 X% G- c }
' ]( z i4 v" J+ p& a void clock()
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uchar i=0;' H# b; P+ M: Q$ ]8 f) G \$ Q7 o
scl=1; flash();; r( ~; Z2 e* Y; W9 X9 Y+ p/ K
while ((sda==1)&&(i<255))i++;
; C( C: `2 T5 G5 {! A scl=0; flash();
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uchar x24c02_read(uchar address): h3 h1 n7 Z5 g+ p r% ~! o3 V& k
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uchar i; Q& N. a, _! f4 u0 @# |& v
start(); writex(0xa0);! _. y" ~# L! x9 K, q9 o, M7 d7 U
clock(); writex(address);/ z" ^; h0 O8 t, O6 \7 H& |* R9 d( F
clock(); start();
9 _3 {# Z( {6 U' @: o writex(0xa1); clock();" X+ j, W: g" M) @3 X
i=readx(); stop();
& ?: U) X8 d8 p delay1(10);
& y) ^& n0 i/ | S% q return(i);8 a2 C8 w9 Q8 Z2 C/ O0 t) y
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void x24c02_write(uchar address,uchar info)% b3 k+ Y8 E7 k0 k/ k, i1 A
{
1 V- Q! J$ @' P+ H1 Y EA=0;
" d3 r# s* H) m" I! ~5 q start(); writex(0xa0);" O) d& \$ Y4 J( \ z7 w
clock(); writex(address);
5 s% ^) w- W1 u) b+ O( } clock(); writex(info);
! X! v$ i9 Q+ K7 v9 | clock(); stop();
' N7 f- k% K' N6 ~3 i EA=1;
+ B" c3 b3 ?. ?4 D9 \+ n delay1(50);, N% _* h, B# U; m2 g6 T
} |
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