I am trying to trigger an if condition by reading serial port. Its not working. Where am I going wrong? See below my lines of code. I am writing to serial port by typing 1 in serial monitor and pressing enter.
void loop()
{
buttonState1 = digitalRead(buttonPin1);
if (((buttonState1 == HIGH) || (Serial.available() && Serial.read() == 1) ) || (OperationStarted == true))
{
/*stuff happens*/
}
}
Try
(Serial.available() && Serial.read() == "1")
and select No Line Ending at the bottom of the monitor
Or, try
(Serial.available() && Serial.read() == '1')
you're looking at the difference between the integer value 1 in your first comparison, and the int returned by Serial.read(), which will be the ASCII character 1, value 0x31, because that's what you're typing.
This works - tested.
void loop()
{
buttonState1 = digitalRead(buttonPin1);
if (((buttonState1 == HIGH) || (Serial.available() && Serial.parseInt() == 1) ) || (OperationStarted == true))
{
/*stuff happens*/
}
}
This is a democode that goes beyond comparising a single character.
It uses the SafeString-Library which can be installed with the library-manager of the arduino-ide.
The demo-code shows how commands build from multiple characters can be used to execute actions.
// SafeStringReader_Cmds.ino
//
// Example of NON-Blocking read commmands from the Arduino Monitor input and acts on them
// the available commands are start stop
// See the SafeStringReader_CmdsTimed.ino for an example using a struct to hold the commands and their functions
//
// Commands are delimited by space dot comma NL or CR
// If you set the Arduino Monitor to No line ending then the last command will be ignored until it is terminated by a space or ,
// Use the settings Newline or Carrage Return or Both NL & CR
//
// These commands can be picked out of a line of user input
// start stop
// The input line can be as long as you like 100's of Kb long, but only two small buffers need to parse the commands
//
// download and install the SafeString library from
// www.forward.com.au/pfod/ArduinoProgramming/SafeString/index.html
#include "SafeStringReader.h"
// create an sfReader instance of SafeStringReader class
// that will handle commands upto 5 chars long
// delimited by space, comma or CarrageReturn or NewLine
// the createSafeStringReader( ) macro creates both the SafeStringReader (sfReader) and the necessary SafeString that holds input chars until a delimiter is found
// args are (ReaderInstanceName, expectedMaxCmdLength, delimiters)
createSafeStringReader(sfReader, 5, " ,\r\n");
bool running = true;
unsigned long loopCounter = 0;
void setup() {
Serial.begin(115200);
Serial.println( F("Setup-Start") );
Serial.println();
Serial.println( F(" Commands are 'stop' 'start'") );
Serial.println( F(" Set the Arduino IDE monitor to Newline, or Carriage return or Both NL & CR") );
Serial.println( F(" See the SafeStringReader_CmdsTimed.ino for an example using a struct to hold the commands and their functions.") );
SafeString::setOutput(Serial); // enable error messages and SafeString.debug() output to be sent to Serial
if (running) {
Serial.println( F(" Counter Started"));
}
sfReader.connect(Serial); // where SafeStringReader will read from
sfReader.echoOn(); // echo back all input, by default echo is off
}
void handleStartCmd() {
running = true;
Serial.println();
Serial.print( F("> start at Counter:") );
Serial.println(loopCounter);
}
void handleStopCmd() {
running = false;
Serial.println();
Serial.print( F("> stop at Counter:") );
Serial.println(loopCounter);
}
void loop() {
if (sfReader.read()) {
if (sfReader == "start") {
handleStartCmd();
}
else if (sfReader == "stop") {
handleStopCmd();
} // else ignore unrecognized command
} // else no delimited command yet
// rest of code here is executed while the user typing in commands
if (running) {
loopCounter++;
if ((loopCounter % 100000) == 0) { // print the current counter every now and again
Serial.print(F("Counter:")); Serial.println(loopCounter);
}
}
}
best regards Stefan
Using the parseInt() function to read a one-digit code is not a good advice because the internal delay of the parseInt() method.
Just read the char and compare it with '1' , as @camsysca advised - it is much faster and more efficient
And, this is also necessary, unless you build in traps for the line ending characters.
There is no reason to call Serial.available(), Serial.read() will return an integer value of -1 if no character has been received.
@camsysca this works. But I am not able to stop the process initiated (the process is printing data to serial) by the following code.
if (((buttonState1 == HIGH) || (Serial.available() && Serial.read() == '1') ) || (OperationStarted == true))
{
/*stuff (serial prints) happens*/
}
else if ((Serial.read() == '0'))
{
/*stuff (prints to serial) is topped from happening*/
}
Can you elaborate why this is necessary? I would be eventually communicating via a desktop application, I would like to know what additional settings I'll need to apply in that application.
@StefanL38 thanks for sharing this. So one needs to just put the /stuff happens/ part of the code here?
void handleStartCmd() {
running = true;
/*stuff Happens*/
}
Your description "stuff happends" is too unprecise.
Shall the stuff happen only ONCE per serial command
or
Shall the stuff happen CONTINIOUSLY ALL THE TIME until you send a stop-command?
There is analog data being printed to serial continuously for 30-50 seconds. But I'd like to have the ability to stop it whenever I want, hence my attempt at writing stop command along with start command.
ok resolved. I should have triggered if statement in both cases, not else if.
do please clarify this
Every time that you type a '1', then hit enter, your character is followed by either a carriage return, a line feed, both, or neither, depending upon that setting.
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