我有一个Arduino的I²C总线连接到Microchip PICDEM 2板的I²C总线,以编程其32K字节的EEPROM。下面的代码有一个读取问题。具体来说,我用16位计数模式编写了整个EEPROM,并验证所有数据都是正确的。
以下代码由PC上的Java程序驱动。我正在读写16字节的页面。我监控了来自PC的地址,它们都是正确的。除了0x0AXX
处的256字节地址块之外,返回的数据都是正确的。读取的数据类似于0x9F0
中的行。我无法弄清楚错误发生的原因。
#include "Wire.h"
const int bufsize = 68;
char ibuf[bufsize];
int bytecnt;
int result;
void setup() {
Wire.begin();
Serial.begin(9600);
}
void i2c_init() {
Wire.begin();
}
void i2c_write( int addr, int count ){
Wire.beginTransmission( addr );
for(int i=0;i<count;i++) {
Wire.write(ibuf[3+i]);
}
result = Wire.endTransmission();
delay(20);
Serial.write(result);
}
void i2c_read( int addr, int count ){
result = Wire.requestFrom( addr, count );
Serial.write( result );
}
void i2c_xfer( int count ){
for(int i=0; i<count; i++ ){
Serial.write( Wire.read() );
}
}
void loop() {
// Accept a line of input
bytecnt = Serial.readBytesUntil('\n', ibuf, bufsize);
if ( bytecnt > 0 ) {
switch( ibuf[0] ) {
case 0: i2c_init(); break;
case 1: i2c_write(ibuf[1],ibuf[2]); break;
case 2: i2c_read(ibuf[1],ibuf[2]); break;
case 3: i2c_xfer(ibuf[1]); break;
default: break;
}
}
}
PC接收的数据全部正确,但以下块除外:
09c0 e0 04 e1 04 e2 04 e3 04 e4 04 e5 04 e6 04 e7 04
09d0 e8 04 e9 04 ea 04 eb 04 ec 04 ed 04 ee 04 ef 04
09e0 f0 04 f1 04 f2 04 f3 04 f4 04 f5 04 f6 04 f7 04
09f0 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a00 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a10 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a20 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a30 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a40 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a50 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a60 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a70 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a80 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0a90 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0aa0 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0ab0 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0ac0 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0ad0 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0ae0 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0af0 f8 04 f9 04 fa 04 fb 04 fc 04 fd 04 fe 04 ff 04
0b00 80 05 81 05 82 05 83 05 84 05 85 05 86 05 87 05
0b10 88 05 89 05 8a 05 8b 05 8c 05 8d 05 8e 05 8f 05
0b20 90 05 91 05 92 05 93 05 94 05 95 05 96 05 97 05
此块之前和之后的所有内容都很好,但0x0A00 - 0x0AFF重复行0x09F0中的数据。以下代码用于编写和验证所有计数模式:
#include "Wire.h"
int EEPROM = 0x50;
int pageSize = 0x10;
unsigned int length = 0x8000;
unsigned int addr = 0;
unsigned int data = 0;
unsigned int datah = 0;
unsigned int datal = 0;
int result;
unsigned int i;
unsigned int r;
long j;
int k;
int errors;
void setup() {
Wire.begin();
Serial.begin(9600);
}
void eeprom_check() {
for(i=0; i<length; i+=pageSize) {
// Write to set address pointer
Wire.beginTransmission( EEPROM );
Wire.write( (i>>8) & 0xFF );
Wire.write( i & 0xFF );
Wire.endTransmission();
if(( i & 0xfF ) == 0 ) {
Serial.write('\n');
Serial.print( i,HEX);
Serial.write(": ");
}
errors = 0;
result = Wire.requestFrom( EEPROM, pageSize );
for(j=0; j<8; j++) {
datal = Wire.read();
datah = Wire.read();
data = (i>>1)+j;
if( datal != (data & 0xFF) )
errors += 1;
if( datah != ( (data>>8) & 0xFF) )
errors += 1;
}
if( errors > 0 )
Serial.write('X');
else
Serial.write('_');
}
}
void eeprom_dump() {
for(i=0; i<length; i+=pageSize) {
// Write to set address pointer
Wire.beginTransmission( EEPROM );
Wire.write( (i>>8) & 0xFF );
Wire.write( i & 0xFF );
Wire.endTransmission();
if(( i & 0xF ) == 0 ) {
Serial.write('\n');
Serial.print( i,HEX);
Serial.write(": ");
}
result = Wire.requestFrom( EEPROM, pageSize );
for(j=0; j<result; j++) {
data = Wire.read();
if( data < 16 ){
Serial.print('0');
Serial.print(data,HEX);
}
else {
Serial.print(data,HEX);
}
Serial.print(' ');
}
}
}
void eeprom_write() {
for(i=0; i<length; i+=pageSize) {
for(k=0; k<10; k++){
Wire.beginTransmission( EEPROM );
Wire.write( (i>>8) & 0xFF );
Wire.write( i & 0xFF );
for(j=0; j<8; j++ ){
data = (i>>1)+j;
Wire.write( data & 0xFF );
Wire.write( (data>>8) & 0xff );
}
result = Wire.endTransmission();
delay(10);
if( result==0 )
break;
else
Serial.write(result);
}
k = i / pageSize;
if(( k & 0xF ) == 0 ) {
Serial.write('\n');
Serial.print( i,HEX);
Serial.write(": ");
}
Serial.write('W');
}
}
void eeprom_break() {
i = 0xa00;
Wire.beginTransmission( EEPROM );
Wire.write( (i>>8) & 0xFF );
Wire.write( i & 0xFF );
Wire.write( 0x55 );
Wire.write( 0xAA );
Wire.endTransmission();
Serial.write("Break Compelted\n");
}
void loop() {
char ch;
Serial.write("Interactive EEPROM Test Tool\n");
while( true ) {
Serial.write('>');
while( Serial.available() == 0 );
ch = Serial.read();
Serial.write( ch );
Serial.write('\n');
while( Serial.available() != 0)
Serial.read();
switch( ch ) {
case 'c': eeprom_check(); break;
case 'd': eeprom_dump(); break;
case 'w': eeprom_write(); break;
case 'z': eeprom_break(); break;
default: break;
}
}
}
我这几天一直在努力。任何见解将不胜感激。
答案 0 :(得分:0)
问题解决了(经过很长时间)!
Java程序以一条线形式向Arduino发送命令,该行以命令作为单个数字开头,后跟一系列字节和CR。而已! 当地址是0x0A ?? 0A是CR,它会截断我的命令!我觉得很傻。