Adding kill-switch on boot (pressing any button); more buttons

Author: emanuelen5

pico/boot.py

@@ -5,15 +5,19 @@
 import board
 import digitalio
 import storage
-from buttons import btns, pins
+from buttons import btns, pins, CONFIG_BUTTON
+import sys
 
-print(f"Checking if btn[0]={pins[0]} is pressed.")
+print(f"Checking that no buttons are pressed at boot.")
 
 # If write pin is connected to ground on start-up, CircuitPython can write to CIRCUITPY filesystem.
-if not btns[0].value:
+if not CONFIG_BUTTON.value:
     print("Mounting as read-only for host! Disabling storage and serial port.")
     storage.remount("/", readonly=False)
     storage.disable_usb_drive()
     usb_cdc.disable()
+elif not all(btn.value for btn in btns):
+    print("Not all buttons were 'up'. Exiting")
+    sys.exit(-1)
 else:
     print("Not pressed. Starting in RW mode.")

pico/buttons.py

@@ -1,10 +1,12 @@
 import board
 import digitalio
 
-pins = [board.GP0, board.GP1]
+pins = [board.GP0, board.GP1, board.GP2, board.GP3, board.GP4, board.GP5]
 btns = []
 for pin in pins:
     btn = digitalio.DigitalInOut(pin)
     btn.direction = digitalio.Direction.INPUT
     btn.pull = digitalio.Pull.UP
     btns.append(btn)
+
+CONFIG_BUTTON = btns[0]

pico/code.py

@@ -5,7 +5,8 @@
 import board
 import digitalio
 import json
-from buttons import btns, pins
+import sys
+from buttons import btns, pins, CONFIG_BUTTON
 BUTTON_COUNT = len(btns)
 
 print("Starting")
@@ -18,6 +19,13 @@
 
 keyboard = Keyboard(usb_hid.devices)
 
+
+if not CONFIG_BUTTON.value:
+    print("Don't care about the config button. It only has special meaning for the boot script.")
+if not all(btn.value for btn in btns):
+    print("Not all buttons were 'up'. Exiting")
+    sys.exit(-1)
+
 try:
     with open("config.json", "rt") as f:
         config = json.load(f)

pico/config.json

@@ -1 +1 @@
-[["ALT", "TAB"], null]
+[["A"], ["B"], ["C"], ["D"], ["E"], ["F"]]