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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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8 _3 R# a4 x# A* c2 P( l #define uchar unsigned char$ w" k- A- o' Y+ z. z
#define uint unsigned int% }! J' h( {1 G/ {$ M& [% t; @4 ]4 H
#include <reg52.h>
5 j4 j" P* ]6 l #include <stdio.h>
/ A5 E: K2 t# f9 o' O; m# }# l #include <absacc.h>
/ [1 q x" {6 V sbit scl=P3^5; //24c02 SCL
# J1 _" ?5 A$ N1 t6 d; y5 V sbit sda=P3^4; //24c02 SDA8 ?& y7 H( n" V0 J
sbit DOG=P1^7; //狗& p N' p1 _ r, k
uchar x24c02_read(uchar address); //从24c02的地址address中读取一个字节数据+ e; ~8 K) Z! V' r5 X( ?
void x24c02_write(uchar address,uchar info);
" P( K0 P0 a8 z6 {9 k0 t) [: i& I //向24c02的address地址中写入一字节数据info
% ~" H2 ^: V2 T; [& V4 h0 C5 \ void x24c02_init(); //24c02初始化子程序* z) K! }1 [) \# _. `0 i5 b5 P
void delay1(uchar x);% ^! H8 ~* ~& y; E0 g! x ~
void flash();
u1 D9 g# z9 I2 F# |; l) Z1 M void x24c01_init();, q2 D: `% M# ]) U* j
void start();3 `7 c+ R8 p2 J
void stop();3 F; x6 [; l3 b* j. d, P
void writex(uchar j);7 |0 S Q; D1 q y
uchar readx();
% x+ N7 `. n. [1 h7 \6 s void clock();5 X' j& \! Y! ?
void delay1(uchar x)
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uint i;/ _3 T# X4 @* ?3 e
for(i=0;i<x;i++);
" a' n+ K. i0 R9 K" w" J+ H) _ DOG=~DOG;
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- d4 h+ F( {& S" U$ Y$ O( I void flash()
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uchar u;
& [$ W7 \- l. ?2 A5 P% n0 z( J) s* E DOG=~DOG;# [( B+ B8 E0 ~, G
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void x24c02_init(): I& y6 N* S. h, ]4 m }& _7 ]
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scl=1; flash(); sda=1; flash();! F8 d0 p6 x7 S
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void start()* ^ f$ ~, `4 [$ a1 n1 M
{
1 D* o' d/ d# r G! [" ?9 } sda=1; flash(); scl=1; flash(); sda=0; flash(); scl=0; flash();
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void stop()! [) ~5 x& J4 f0 B, Q1 D
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sda=0; flash(); scl=1; flash(); sda=1; flash();
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/ g) r& k) l- E* w" K$ i void writex(uchar j)
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uchar i,temp;) d5 D1 b3 r( z3 [* d
temp=j;8 c; x! [7 Z+ a s% A% D% I" @8 Z
for (i=0;i<8;i++){
0 b) D6 }/ E( J" q, f9 H& H5 X temp=temp<<1; scl=0; flash(); sda=CY; flash(); scl=1; / D0 d/ h! k4 E/ k$ u
flash();/ e. T" l4 N5 ]. z8 [& |
}
/ \! b* Z3 }" O; b0 L& I5 \% o$ I scl=0; flash(); sda=1; flash();# g& w5 a4 [; q7 N- V
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uchar readx()
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1 F6 ?. S0 c) ]4 R" h- B5 O uchar i,j,k=0;0 A- Q1 \+ U9 [8 O4 A% Y3 E( U6 X h7 a
scl=0; flash(); sda=1;
- E1 k' w/ r: G for (i=0;i<8;i++){. k$ H# K; m/ J t+ U0 T6 @- |% r
flash(); scl=1; flash();
4 {7 @# G) X' P! S. s2 P if (sda==1) j=1;. P0 A. s- Q; O) f) D9 |8 ^
else j=0;
$ X% h- E% U" h* ^ k=(k<<1)|j; scl=0;5 o$ ]1 j& @3 B: E
}
S" X4 y. r3 `# Q+ q% ^ flash(); return(k);
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9 J0 g1 x$ M$ t$ N# \2 a7 ^* [* s void clock()
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uchar i=0;
2 @( ^ b& j2 d# s# k! I scl=1; flash();; T6 V* i5 I1 v
while ((sda==1)&&(i<255))i++;
0 m( |1 n. V) g. S) { scl=0; flash();
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uchar x24c02_read(uchar address)
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3 m& R$ T% K/ a' e2 p( ] uchar i;
h1 C4 l( Y. q% V4 y start(); writex(0xa0);
9 U* Y/ C* F2 v) v clock(); writex(address);4 x) g0 X8 p8 h4 T% R7 \
clock(); start();2 x. G8 M5 A/ m. G/ j6 s
writex(0xa1); clock();0 j' V- o2 ?/ F, u" d+ S6 W; F
i=readx(); stop();/ @5 x, V9 f5 U* f; o: e
delay1(10);; w# S1 S4 |* T k' S& I
return(i);
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void x24c02_write(uchar address,uchar info)) [. }' [/ V, ^3 x% p! \# s+ K, W
{! N2 e; O- g8 y! e
EA=0;
0 [: r$ f& V9 j% ^+ d0 z start(); writex(0xa0);
5 A. f+ L/ {1 Q6 Q' J$ Z clock(); writex(address);
# {; l1 i( Q6 ?2 g& L4 K9 w clock(); writex(info);
9 d1 k9 n( ^' g# N% u) ` clock(); stop();0 A# z& U `$ o5 r' }
EA=1;* r- g3 a( m9 h. n6 F
delay1(50);- x# d0 J9 j/ _# O, z! i
} |
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