Arduino 1 没有正确读取串口监视器的字符串
Arduino 1 not reading correctly the string from Serial Monitor
Arduino Uno 上的串行监视器有问题。
基本上我想在串口监视器上写一些命令,读取字符串并根据字符串做一些事情。
问题如下:假设我在串行监视器中键入命令 'read 4',有时字符串被正确读取,有时它被读取为:'ead 4',缺少第一个字符。
我什至在串行监视器的两个读数之间设置了延迟。有人有解释吗?
为了完整性,我 post 我的代码(基本上是 reads/writes from/to EEPROM:例如 'read 5' 将读取 EEPROM 的第 5 块,'write 4 5' 会将值 5 写入第 4 个内存块)。
#define MAX_STRING_LENGTH 14
#include <ctype.h>
#include <EEPROM.h>
//The function initializes the string to spaces
void initString(char* mystr, char strLength);
//The function returns true if it is a read operation, false otherwise
boolean isReadEEPROM(char *myStr, char strLength);
//The function returns true if it is a write operation, false otherwise
boolean isWriteEEPROM(char *myStr, char strLength);
//The function returns the EEPROM address from the string
unsigned int findAddress(char *myStr, char strLength);
char findValue(char *myStr, char strLength);
//Check the address range
boolean isAddressOk(unsigned int address);
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
}
void loop() {
char pos = 0;
bool newDataFound = false;
char serialStr[MAX_STRING_LENGTH];
unsigned int address = 0;
char val = 0;
while(Serial.available()){
val = Serial.read();
}
val = 0;
initString(&serialStr[0], (char) MAX_STRING_LENGTH);
while(Serial.available() && pos < MAX_STRING_LENGTH){
serialStr[pos] = Serial.read();
pos ++;
newDataFound = true;
delay(200);
}
if (newDataFound){
Serial.print("New Command found: ");
Serial.println(serialStr);
address = 0;
address = findAddress(&serialStr[0], MAX_STRING_LENGTH);
if (isReadEEPROM(&serialStr[0], MAX_STRING_LENGTH) && isAddressOk(address)){
Serial.println("Reading from EEPROM");
Serial.print("Address is ");
Serial.println(address);
val = EEPROM.read(address);
Serial.print("Value is: ");
Serial.println( (uint8_t) val );
Serial.println(" ");
}
else if (isWriteEEPROM(&serialStr[0], MAX_STRING_LENGTH) && isAddressOk(address)){
Serial.println("Writing to EEPROM");
Serial.print("Address is ");
Serial.println(address);
Serial.println(" ");
val = findValue(&serialStr[0], MAX_STRING_LENGTH);
EEPROM.write(address, val);
}
else{
if (!isAddressOk(address)){
Serial.write(address);
Serial.println("Address out of range");
Serial.println("");
}
Serial.println("Not recognized operation\n");
}
delay(2000);
}
}
void initString(char* mystr, char strLength){
for(char ii=0; ii<strLength; ii++){
(*mystr) = ' ';
mystr++;
}
}
//The function returns true if it is a read operation, false otherwise
boolean isReadEEPROM(char *myStr, char strLength){
//The string should contain first the 'read' operation
char expected[] = "read";
int ii =0;
while (ii<4){
if ( *(myStr + ii) != expected[ii]){
return false;
Serial.println("Not a Read Operation\n");
}
ii++;
}
return true;
Serial.println("Read Operation");
}
//The function returns true if it is a write operation, false otherwise
boolean isWriteEEPROM(char *myStr, char strLength){
//The string should contain first the 'read' operation
char expected[] = "write";
int ii =0;
while (ii<5){
if ( *(myStr + ii) != expected[ii]){
return false;
}
ii++;
}
return true;
}
//The function returns the EEPROM address from the string
unsigned int findAddress(char *myStr, char strLength){
unsigned int address;
char tmpStr[strLength];
char strAddress[] = " ";
int ii = 0;
while(ii< strLength){
tmpStr[ii] = *(myStr+ii);
ii++;
}
Serial.print("The address found is: ");
Serial.println(strAddress);
ii= 0;
if (isReadEEPROM(myStr, strLength)){
while (ii<=4){
if (isdigit(*(myStr + 5 + ii))){
strAddress[ii] = *(myStr + 5 + ii);
}
else{
break;
}
ii++;
}
address = atoi(strAddress);
}
else if(isWriteEEPROM(myStr, strLength)){
while (ii<=4){
if (isdigit(*(myStr + 6 + ii))){
strAddress[ii] = *(myStr + 6 + ii);
}
else{
break;
}
ii++;
}
address = atoi(strAddress);
}
else{
address = 0;
//Serial.println("Address not available in function 'findAddress'");
}
return address;
}
//The function returns the value to be written to the EEPROM from the string
char findValue(char *myStr, char strLength){
char val;
char tmpStr[strLength];
char strVal[] = " ";
int ii, idx = 0;
while(ii< strLength){
tmpStr[ii] = *(myStr+ii);
ii++;
}
ii= 0;
// first found the first digits corresponding to the address
while (ii<=4){
if (isdigit(*(myStr + 6 + ii))){
;//strAddress[ii] = *(myStr + 6 + ii);
}
else{
ii++;
break;
}
ii++;
}
// now find the value
while (ii<=4+3){
Serial.println(*(myStr + 6 + ii));
if (isdigit(*(myStr + 6 + ii))){
strVal[idx] = *(myStr + 6 + ii);
}
else{
break;
}
ii++;
idx++;
}
Serial.print("original string: ");
Serial.println(tmpStr);
Serial.print("Value found: ");
Serial.println(strVal);
val = (char)atoi(strVal);
return val;
}
boolean isAddressOk(unsigned int address){
if (address < 1024 && address >= 0){
return true;
}
else{
return false;
}
}
这段代码:
char val=0;
while(Serial.available()){
val = Serial.read();
}
val = 0;
正在消耗可能留在输入缓冲区中的任何字符。你也可以这样做:
while (Serial.avaialble())
Serial.read();
下一个while循环不会等待整个命令。有时,它获得了 'r',然后没有及时获得 'ead...'。下次 loop
执行时它们会在那里,所以看起来 'r' 不见了。之前loop
.
刚消耗完
通过 USB(从串行监视器 window)发送的内容可能会有奇怪的延迟。
要收集 完整的 行,您应该保存字符直到收到“\n”:
for (;;) {
if (Serial.available()) {
char c = Serial.read();
if (c == '\n')
break;
if (pos < MAX_LINE_LENGTH) {
serialStr[pos] = c;
pos ++;
}
newDataFound = true;
}
}
delay
调用完全没有必要,因为 for
循环会一直等待,直到接收到 '\n' 字符(确保在串行监视器下拉菜单中 'New Line' 或 'both NL & CR' 被选中)。那么您就知道您已经阅读了该行中的所有字符。
Arduino Uno 上的串行监视器有问题。
基本上我想在串口监视器上写一些命令,读取字符串并根据字符串做一些事情。
问题如下:假设我在串行监视器中键入命令 'read 4',有时字符串被正确读取,有时它被读取为:'ead 4',缺少第一个字符。 我什至在串行监视器的两个读数之间设置了延迟。有人有解释吗?
为了完整性,我 post 我的代码(基本上是 reads/writes from/to EEPROM:例如 'read 5' 将读取 EEPROM 的第 5 块,'write 4 5' 会将值 5 写入第 4 个内存块)。
#define MAX_STRING_LENGTH 14
#include <ctype.h>
#include <EEPROM.h>
//The function initializes the string to spaces
void initString(char* mystr, char strLength);
//The function returns true if it is a read operation, false otherwise
boolean isReadEEPROM(char *myStr, char strLength);
//The function returns true if it is a write operation, false otherwise
boolean isWriteEEPROM(char *myStr, char strLength);
//The function returns the EEPROM address from the string
unsigned int findAddress(char *myStr, char strLength);
char findValue(char *myStr, char strLength);
//Check the address range
boolean isAddressOk(unsigned int address);
void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
}
void loop() {
char pos = 0;
bool newDataFound = false;
char serialStr[MAX_STRING_LENGTH];
unsigned int address = 0;
char val = 0;
while(Serial.available()){
val = Serial.read();
}
val = 0;
initString(&serialStr[0], (char) MAX_STRING_LENGTH);
while(Serial.available() && pos < MAX_STRING_LENGTH){
serialStr[pos] = Serial.read();
pos ++;
newDataFound = true;
delay(200);
}
if (newDataFound){
Serial.print("New Command found: ");
Serial.println(serialStr);
address = 0;
address = findAddress(&serialStr[0], MAX_STRING_LENGTH);
if (isReadEEPROM(&serialStr[0], MAX_STRING_LENGTH) && isAddressOk(address)){
Serial.println("Reading from EEPROM");
Serial.print("Address is ");
Serial.println(address);
val = EEPROM.read(address);
Serial.print("Value is: ");
Serial.println( (uint8_t) val );
Serial.println(" ");
}
else if (isWriteEEPROM(&serialStr[0], MAX_STRING_LENGTH) && isAddressOk(address)){
Serial.println("Writing to EEPROM");
Serial.print("Address is ");
Serial.println(address);
Serial.println(" ");
val = findValue(&serialStr[0], MAX_STRING_LENGTH);
EEPROM.write(address, val);
}
else{
if (!isAddressOk(address)){
Serial.write(address);
Serial.println("Address out of range");
Serial.println("");
}
Serial.println("Not recognized operation\n");
}
delay(2000);
}
}
void initString(char* mystr, char strLength){
for(char ii=0; ii<strLength; ii++){
(*mystr) = ' ';
mystr++;
}
}
//The function returns true if it is a read operation, false otherwise
boolean isReadEEPROM(char *myStr, char strLength){
//The string should contain first the 'read' operation
char expected[] = "read";
int ii =0;
while (ii<4){
if ( *(myStr + ii) != expected[ii]){
return false;
Serial.println("Not a Read Operation\n");
}
ii++;
}
return true;
Serial.println("Read Operation");
}
//The function returns true if it is a write operation, false otherwise
boolean isWriteEEPROM(char *myStr, char strLength){
//The string should contain first the 'read' operation
char expected[] = "write";
int ii =0;
while (ii<5){
if ( *(myStr + ii) != expected[ii]){
return false;
}
ii++;
}
return true;
}
//The function returns the EEPROM address from the string
unsigned int findAddress(char *myStr, char strLength){
unsigned int address;
char tmpStr[strLength];
char strAddress[] = " ";
int ii = 0;
while(ii< strLength){
tmpStr[ii] = *(myStr+ii);
ii++;
}
Serial.print("The address found is: ");
Serial.println(strAddress);
ii= 0;
if (isReadEEPROM(myStr, strLength)){
while (ii<=4){
if (isdigit(*(myStr + 5 + ii))){
strAddress[ii] = *(myStr + 5 + ii);
}
else{
break;
}
ii++;
}
address = atoi(strAddress);
}
else if(isWriteEEPROM(myStr, strLength)){
while (ii<=4){
if (isdigit(*(myStr + 6 + ii))){
strAddress[ii] = *(myStr + 6 + ii);
}
else{
break;
}
ii++;
}
address = atoi(strAddress);
}
else{
address = 0;
//Serial.println("Address not available in function 'findAddress'");
}
return address;
}
//The function returns the value to be written to the EEPROM from the string
char findValue(char *myStr, char strLength){
char val;
char tmpStr[strLength];
char strVal[] = " ";
int ii, idx = 0;
while(ii< strLength){
tmpStr[ii] = *(myStr+ii);
ii++;
}
ii= 0;
// first found the first digits corresponding to the address
while (ii<=4){
if (isdigit(*(myStr + 6 + ii))){
;//strAddress[ii] = *(myStr + 6 + ii);
}
else{
ii++;
break;
}
ii++;
}
// now find the value
while (ii<=4+3){
Serial.println(*(myStr + 6 + ii));
if (isdigit(*(myStr + 6 + ii))){
strVal[idx] = *(myStr + 6 + ii);
}
else{
break;
}
ii++;
idx++;
}
Serial.print("original string: ");
Serial.println(tmpStr);
Serial.print("Value found: ");
Serial.println(strVal);
val = (char)atoi(strVal);
return val;
}
boolean isAddressOk(unsigned int address){
if (address < 1024 && address >= 0){
return true;
}
else{
return false;
}
}
这段代码:
char val=0;
while(Serial.available()){
val = Serial.read();
}
val = 0;
正在消耗可能留在输入缓冲区中的任何字符。你也可以这样做:
while (Serial.avaialble())
Serial.read();
下一个while循环不会等待整个命令。有时,它获得了 'r',然后没有及时获得 'ead...'。下次 loop
执行时它们会在那里,所以看起来 'r' 不见了。之前loop
.
通过 USB(从串行监视器 window)发送的内容可能会有奇怪的延迟。
要收集 完整的 行,您应该保存字符直到收到“\n”:
for (;;) {
if (Serial.available()) {
char c = Serial.read();
if (c == '\n')
break;
if (pos < MAX_LINE_LENGTH) {
serialStr[pos] = c;
pos ++;
}
newDataFound = true;
}
}
delay
调用完全没有必要,因为 for
循环会一直等待,直到接收到 '\n' 字符(确保在串行监视器下拉菜单中 'New Line' 或 'both NL & CR' 被选中)。那么您就知道您已经阅读了该行中的所有字符。