Hello everyone.
#include "string.h"
int ledgreen=9;
int tx=1;
void setup(){
pinMode(ledgreen, OUTPUT);
pinMode(tx, OUTPUT);
void loop(){
int i=0;
delay(500);
i++; *
}*_ }}*_
void allpinslow() { digitalWrite(ledgreen, LOW); *} *
void Check_Protocol(char inStr[]){ int i=0;* int m=0;* * Serial.println(inStr);*
* if(!strcmp(inStr,"gon")){ //Ledgreen ON* * allpinslow();* * digitalWrite(ledgreen, HIGH);* * Serial.println("Green ON");* * for(m=0;m<11;m++){* * inStr[m]=0;}* * i=0;}* else if(!strcmp(inStr,"goff")){ //Ledgreen OFF * allpinslow();* * digitalWrite(ledgreen, LOW);* * Serial.println("Green OFF");* * for(m=0;m<11;m++){* * inStr[m]=0;}* * i=0;}*
* else{* * for(m=0;m<11;m++){* * inStr[m]=0;* * }* * i=0;* }}
please use code tags.... half of the code is now italic
What is the output of the sketch?
Please post the input also.
You can still change your post and add code tags around the code.
See #7 of How to use this forum
pinMode(tx, OUTPUT);
pinMode(rx, INPUT);
Why ?
What have you got the line ending set to in the Serial Monitor ? If it is CR, LF or both then they will be included in the received string.
system
October 17, 2015, 12:19pm
5
strcmp() returns 0 if the strings match, and returns +1 or -1 depending on which string comes first in the dictionary if they do not match. You are assuming that true means that they match. That is wrong.
@PaulS : where did you see that?
tarandeep:
if(!strcmp(inStr,"gon")){ //Ledgreen ON
}
but probably the follow would work better anyway (if there is more in the buffer)
if(!strncmp(inStr, "gon", 3)){ //Ledgreen ON
} else if(!strncmp(inStr, "goff", 4)){ //Ledgreen OFF
system
October 17, 2015, 1:09pm
7
where did you see that?
I missed the ! in that statement. I never write calls to strcmp() that way.
if(strcmp("this", "that") == 0)
{
// The computer is broken
}
is just easier for me to follow.
PaulS:
almost right , the spec - http://www.cplusplus.com/reference/cstring/strcmp/ - states
strcmp() compare the chars at subsequent positions and returns the diff if unequal
int strcmp(const char* s1, const char* s2)
{
while(*s1 && (*s1==*s2))
s1++,s2++;
return *(const unsigned char*)s1-*(const unsigned char*)s2;
}
Assume this done to minimize footprint / maximize performance.
I do not know of any application that uses this difference (as it is not known at which position it is)
system
October 17, 2015, 3:06pm
9
OK. I should have said strcmp() returns A positive or negative value, depending on the dictionary order,if the two strings are not equal.
I agree that using the return value to do anything useful, other then in the positive, zero, or negative sense for sorting, would be unusual.
The -1 0 1 of the compare function return values are used for sorting.
This will never work:
char inSerial[15];
...
inSerial=Serial.read();
i++;
}
inSerial='\0';
You need to index into the array inSerial[].
@jremington : the [ i ] were probably interpreted and removed outside the code tags.
Thanks. I wasted only a minute or two.
@jremington : I had the supected that error too, even tried to make the OP add the tags to remove that ambiguity, but failed.n cmp.
With the array index added to the original code it works as long as only gon or goff are sent. If an LF or CR are included then, no surprise, it doesn't.
