nano_nora: fix: reset all matrix connections at boot

Author: pillo79

variants/arduino_nano_nora/variant.cpp

@@ -5,6 +5,28 @@
 
 extern "C" {
     void initVariant() {
+        // FIXME: fix issues with GPIO matrix not being soft reset properly
+        for (int pin = 0; pin<NUM_DIGITAL_PINS; ++pin) {
+            switch (pin) {
+                case LED_RED:
+                case LED_GREEN:
+                case LED_BLUE:
+                    // set RGB pins to dig outputs, HIGH=off
+                    pinMode(pin, OUTPUT);
+                    digitalWrite(pin, HIGH);
+                    break;
+
+                case TX:
+                case RX:
+                    // leave UART pins alone
+                    break;
+
+                default:
+                    // initialize other pins to dig inputs
+                    pinMode(pin, INPUT);
+                    break;
+            }
+        }
     }
 }