How do you confirm that your OS can see the Core?
What OS are you running?
If Windows, have you installed the driver mentioned here?
If you use the Spark Dev Serial Monitor, you have to type in a letter and send it with Enter
To see if your keypress reaches the Core try to add this after your first while() loop
pinMode(D7, OUTPUT);
digitalWrite(D7, HIGH);
and at the end of setup() add
delay(500);
digitalWrite(D7, LOW);
So if the blue LED lights up the keypress reaches the Core, if it goes off again your setup() finishes and the Core will execute loop() regularly.
If it never goes on you are not really seeing the Core from your serial monitor.
I’d also add SPARK_WLAN_Loop(); inside your while(1) to allow a reflash without reset.
For testing you should always add some additional means to distinguish how far your code works and where it fails.
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