Hi there,
I am happy to share the relevant part of the Arduino code but sadly I probably can't share it all without my supervisor's permission. I will attach it in an edit to this post. It is worth nothing however that as I have said, the Arduino responds immediately to exactly the same commands written via NI MAX and/or Arduino IDE, so I am 99% sure the issue is not with the Arduino code.
1. That's good advice, I will follow that.
2. I had just thrown it in there as part of my troubleshooting, so I will remove it again as I am fairly sure it made no difference.
Thank you so much for your help,
Sam
Edit 1: Interestingly, in the code I provided, only the wait before the write is needed - no wait is needed between writing the command and reading the response! This leads me to think the issue arises from writing too soon, the command doesn't reach the arduino, so the read just times out because nothing is sent back if no command is received?
Edit 2: The relevant Arduino code:
const byte numChars = 32;
char receivedChars[numChars];
char tempChars[numChars]; // temporary array for use when parsing
// variables to hold the parsed data
char messageFromPC1[numChars] = {0};
char messageFromPC2[numChars] = {0};
boolean newData = false;
unsigned long integerFromPC = 0;
float floatFromPC = 0.0;
String decision;
String instruction;
// string_search();
recvWithEndMarker();
if (newData == true) {
strcpy(tempChars, receivedChars); // this temporary copy is necessary to protect the original data because strtok() used in parseData() replaces the commas with \0
parseData();
showParsedData();
newData = false;
}
void parseData() { // split the data into its parts
char * strtokIndx; // this is used by strtok() as an index
strtokIndx = strtok(tempChars,","); // get the first part - the string
strcpy(messageFromPC1, strtokIndx); // copy it to messageFromPC
strtokIndx = strtok(NULL, ","); // this continues where the previous call left off
integerFromPC = atol(strtokIndx); // convert this part to an integer
strtokIndx = strtok(NULL, ",");
// floatFromPC = atof(strtokIndx); // convert this part to a float
strcpy(messageFromPC2, strtokIndx);
instruction = String(messageFromPC1);
decision = String(messageFromPC2);
}
if (instruction=="read_diff")
{
diff = preset - total;
Serial.print(diff);
Serial.print("\n");
}
if (instruction=="read_total")
{
Serial.print(total);
Serial.print("\n");
}
if (instruction=="read_preset")
{
Serial.print(preset);
Serial.print("\n");
}
if (instruction=="read_pulse_count")
{
Serial.print(pulse_count);
Serial.print("\n")
}
------
I didn't write this code, and like I said the issue does not arise when sending commands over serial, so I am confident the Arduino code is not the issue.
Samuel Allen
University of St Andrews
