Compiler doesn't like function code

Question

I am getting this error from the Visual Studio compiler (I use the Visual Studio add-in Visual Micro for Arduino).

ModelRailroadCrossingSignalController.ino:In function 'void loop() ModelRailroadCrossingSignalController.ino:210:15: error: too few arguments to function 'Adafruit_VS1053_FilePlayer onSignalSound(Adafruit_VS1053_FilePlayer, const char*) :onSignalSound() ModelRailroadCrossingSignalController.ino:note declared here :Adafruit_VS1053_FilePlayer onSignalSound(Adafruit_VS1053_FilePlayer mp, const char* fileName) { Error compiling project sources

Here is the function and loop (all the defines and instances left out for brevity, they aren't the issue

void loop() {
// put your main code here, to run repeatedly
signalEntrySensor = checkEntrySensor();
if (signalEntrySensor == true) {
 if (crossingSignalInOperation == false)
 {
 Adafruit_VS1053_FilePlayer mp = onSignalSound(musicPlayer,"Trainxng.mp3"); //all other functions are called in the sound routine?
 if (debugMode)
 {
 Serial.println("Sound byte called");
 }
 while (mp.playingMusic) {
 // file is now playing in the 'background' so now's a good time
 // to do something else 
 offRoadPower();
 lowerSignalArms();
 onSignalSound();
 startSignalFlashers();
 crossingSignalInOperation = true;
 } 
 }
}
Adafruit_VS1053_FilePlayer onSignalSound(Adafruit_VS1053_FilePlayer mp, const char* fileName) {
// Play the train crossing sound file
if (debugMode)
{
 Serial.println(F("Playing track - "));
 Serial.print(fileName);
}
//all sound files are on the micro sd card on the music player shield
if (!mp.startPlayingFile(fileName)) {
 Serial.println(F("Could not open file "));
 Serial.print(fileName);
 while (1);
}
return mp; }

I'm a C# guy, not ever using C++ until now, but this code should certainly work, not sure why the function is not compiling.

• Nick Gammon: Related: arduino.stackexchange.com/questions/23059/…

Answer 1

The clue is in the error...

too few arguments to function 'Adafruit_VS1053_FilePlayer onSignalSound(Adafruit_VS1053_FilePlayer, const char*)

You have defined the function as this:

Adafruit_VS1053_FilePlayer onSignalSound(Adafruit_VS1053_FilePlayer mp, const char* fileName) {

And yet you then try and call it like this:

onSignalSound();

Spot the mismatch?

I suspect you don't want to be calling that function there since it seems to be in a bit where the sound has already been started.

• dinotom: not sure how i missed that, I had it commented out earlier