I am writing a fairly lengthy program to control my 3d printer heater cabinet.
I have 4 buttons (up, down, enter and back). These are monitored using basically the following line:
if (digitalRead(EnterButton)==HIGH); { << do something >>; }
The buttons are wired how I usually do... 5v high when you push them, with the Arduino pin held low with a 10k resistor.
The entire thing works fine, except in certain circumstances, it reads this digitalRead button as high, even though the pin is obviously low?
For instance, I have a part of the program that runs through a shutdown sequence and I need the option to 'abort shutdown'.
This consists of sounder a piezo, a delay(1000); and printing text to a TFT screen.
If I put then put the digitalRead command after that, it reads it as high, when the pin is low?
Any suggestions?
Is there a known glitch or process on the Arduino that would cause this?
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Well just tried to upload the code and it said too many character (max 9000).
My code isn't pretty... I know that. Its also FAR from completed.
Its not hardware (pretty sure). Its on my development board, so wires are short.
Anyway, the buttons work fine elsewhere in the program.
I had this issue once before and had to program my way around it then.
Here is a snippet of the code...
This works fine. I jump here from the main 'loop', and it returns a variable in Checkbutton depending on the button pressed....
void Checkbuttons () {
if (digitalRead(DownButton)==HIGH) { Checkbutton=1; } //Down button
if (digitalRead(UpButton)==HIGH) { Checkbutton=2; } //Up button
if (digitalRead(EnterButton)==HIGH) { Checkbutton=3; } //If Enter is pressed during main menu
delay(1);
}
This however fails.... it instantly carries out the digitalWrite command after it (it does it whether I ask for digitalRead(EnterButton== High or Low)
void Checkbuttons () {
Checkbutton = 0 ;
if (digitalRead(DownButton)==HIGH) { Checkbutton=1; } //Down button
if (digitalRead(UpButton)==HIGH) { Checkbutton=2; } //Up button
if (digitalRead(EnterButton)==HIGH) { Checkbutton=3; } //If Enter is pressed during main menu
delay(1);
Stevolution:
This however fails.... it instantly carries out the digitalWrite command after it (it does it whether I ask for digitalRead(EnterButton== High or Low)
void Shutdowncancel () {
if (digitalRead(EnterButton)==HIGH); { digitalWrite(ResetIC, HIGH); }
}
Of course it fails You have a semi-colon after the if statement. So the next statement (between the curlies) is not part of the if block and will therefore always be executed.
Stevolution:
Is there a known glitch or process on the Arduino that would cause this?
Why do people always suspect hardware errors The answer to the question is yes and it's called the person behind the keyboard
You have a semi-colon after the if statement. So the next statement (between the curlies) is not part of the if block and will therefore always be executed.