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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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#define uchar unsigned char
- C; p* S1 t! G #define uint unsigned int
+ b [9 Q& R2 e+ I #include <reg52.h>" V( |7 q, W1 d% ?' t
#include <stdio.h>
' k) O; e. y4 B, | #include <absacc.h># p2 }& j; \- U' Q6 x1 ~$ C! F
sbit scl=P3^5; //24c02 SCL
7 \! W% X6 W; L6 N sbit sda=P3^4; //24c02 SDA
% H% Z8 y: U7 e4 P sbit DOG=P1^7; //狗% O+ ]/ z7 y+ P% \- ` k/ k
uchar x24c02_read(uchar address); //从24c02的地址address中读取一个字节数据
. c& u% Z& c3 m void x24c02_write(uchar address,uchar info);
/ B- a, a8 Q/ \1 u, u3 M //向24c02的address地址中写入一字节数据info p- e! q" ]$ c" p
void x24c02_init(); //24c02初始化子程序
% [# D- [% p. u void delay1(uchar x);& b+ N5 D/ s; B& @% }3 t' z, x. G
void flash();3 h8 s3 N- c# r# y% x
void x24c01_init();
5 M* E" {% s7 d- ?8 C- z+ v2 K' h void start();
" r3 m' M" N7 x' \ void stop();
1 C2 y, H# b& e$ ` void writex(uchar j);
& L6 ~- ~* ^' r+ E, p5 U: v uchar readx();
+ x0 v' ^! \; d- C/ a3 W void clock();
. j3 ^$ Q' Q' p0 M1 ?- a void delay1(uchar x)
$ K4 W6 k4 e6 V; s' u7 s$ c {
. U6 Y3 Y/ l. v uint i;
- P5 X6 O4 {. F* D6 Q for(i=0;i<x;i++);
% U* h$ Y& w7 m4 t7 {0 `) q DOG=~DOG;. b* v# c" k; K! D; c0 `2 {# U+ F
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void flash()
: \+ U% W4 E; l7 n/ u, z7 w {
0 b- G+ [' s1 l' [/ p& y uchar u;
7 ?& L e* ]+ U* A DOG=~DOG;2 O" I+ ?8 |; s _
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void x24c02_init()
m1 l1 a! I% a- Q* H1 W$ K$ z {
; q3 V0 K# s2 i) |% q scl=1; flash(); sda=1; flash();% M+ u7 Y! O1 E; |) X8 Z2 m
}
. B2 u6 r1 J" h6 n7 u* f void start()+ G- z, x/ M/ ~$ i3 p% R
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sda=1; flash(); scl=1; flash(); sda=0; flash(); scl=0; flash();! [, s% |. s5 Z4 i+ T: Y# y) o: b
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void stop()
' b5 J* `5 W0 x2 H5 B% `7 I% N! ~ {
' I% {2 u; i( [6 d8 H) D sda=0; flash(); scl=1; flash(); sda=1; flash();0 c0 T3 ^$ }5 y/ l7 }
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void writex(uchar j)4 R" J+ h6 z$ O
{$ v2 }7 b( L4 C
uchar i,temp;
: s+ v9 B7 J* Z$ [' A8 q temp=j;$ k$ x C% x- c, O% f0 O
for (i=0;i<8;i++){# y. ^, q& m' j* ^) n9 r' @
temp=temp<<1; scl=0; flash(); sda=CY; flash(); scl=1;
9 x& l- {7 {; S' m. e! L$ n0 U flash();2 ^8 y0 I# J, y
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scl=0; flash(); sda=1; flash();- M: ^* \2 F" {- u( p4 v
}
+ }4 w8 K' d3 N! i3 | uchar readx()# u( E- J; H- d2 w7 v
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uchar i,j,k=0;& a2 [/ v# a, m1 D
scl=0; flash(); sda=1;" `9 E1 u! Y; c2 x. e, i- o- x
for (i=0;i<8;i++){
! f: K4 E% S! F1 E1 J5 h$ M' k flash(); scl=1; flash();
3 i& z7 p0 S5 {9 X% d P if (sda==1) j=1;
) ` I& t7 A% j! f7 H else j=0;- A3 {7 Z6 F/ p. E3 F+ [; }
k=(k<<1)|j; scl=0;2 i9 u- c {1 e3 y0 Q' P
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flash(); return(k);3 u/ S% O+ m w
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void clock()
" M2 E/ F, b3 h% Q$ [5 A/ g0 } {
5 w4 Q/ p) A, |: `, K uchar i=0; [# j! y3 ^2 B$ y
scl=1; flash();
* d% g4 {% e, B5 C0 x6 [ while ((sda==1)&&(i<255))i++;
- y' }8 q" C$ V scl=0; flash();
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uchar x24c02_read(uchar address)
2 M1 ^ e! b, o" @2 j {
1 } E' ?. y( {4 @2 @; d3 h uchar i;; d7 ?- M! U r: `
start(); writex(0xa0);
* H2 a! w- x% i clock(); writex(address);- p+ s/ q x* b: O, w: t% l
clock(); start();
q" z0 Y! k9 X* f writex(0xa1); clock();$ _5 ^& L4 X' ~. A
i=readx(); stop();
" l3 N3 {2 ^) K1 B delay1(10);
( N8 O" [! t' G- z8 ` X) x return(i);- j2 a/ ~2 ^- ?" J2 E
}
& w/ a. H5 c6 c void x24c02_write(uchar address,uchar info) E% g& h" i( P
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EA=0;" m9 l/ Y. d% e5 j* N, H$ q& A6 n
start(); writex(0xa0);8 p+ S ~) v# f* M9 O
clock(); writex(address);; N! j( K' Q" b& ^+ p" `
clock(); writex(info);
0 T3 ~! @% D2 Z: Y2 o clock(); stop();
1 y& j. i* ?: o3 t; O* ]1 R EA=1;) ~/ G3 Y7 b4 h% ?4 o% N$ ] c$ N
delay1(50);9 D; O% C8 y# r* v5 I! U4 _7 Q( K! k, H. Y
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