Add initial support for reading the "power fault" line

src/Keyboardio-Hardware-Model01.cpp

@@ -35,10 +35,15 @@ void Model01::enable_high_power_leds(void) {
     // PE6
     //    pinMode(7, OUTPUT);
     //    digitalWrite(7, LOW);
-
     DDRE |= _BV(6);
     PORTE &= ~_BV(6);
 
+   // Set B4, the overcurrent check to an input with an internal pull-up
+   DDRB &= ~_BV(4);	// set bit, input
+   PORTB &= ~_BV(4);	// set bit, enable pull-up resistor
+
+
+
 }
 
 void Model01::setup(void) {
@@ -95,6 +100,14 @@ void Model01::led_sync() {
 
 }
 
+boolean Model01::led_power_fault() {
+	if (PINB & _BV(4)) {
+		return true;
+	} else {
+		return false;
+	}
+}
+
 void debug_key_event(keydata_t state, keydata_t previousState, uint8_t keynum, uint8_t row, uint8_t col) {
     if (bitRead(state.all, keynum) != bitRead(previousState.all, keynum )) {
         Serial.print("Looking at row ");

src/Keyboardio-Hardware-Model01.h

@@ -25,6 +25,8 @@ class Model01 {
     void enable_scanner_power(void);
     void reboot_bootloader();
 
+    boolean led_power_fault(void);
+
     uint8_t load_primary_layer(uint8_t layer_count);
     void save_primary_layer(uint8_t layer);