description: > M5Stack Cardputer internal GPIO matrix keyboard: 4 rows x 14 columns, scanned via 3 binary-encoded column-select output pins and 7 row input pins. Exposes a KEYBOARD_TYPE device. Modifier keys (fn/shift/ctrl/opt/alt/tab) are consumed internally and never emitted as their own key events. Regular keys emit their ASCII character (shifted variant when shift or ctrl is held). With fn held: del -> forward delete, enter -> enter, ` -> escape, , -> left, / -> right, ; -> previous (group navigation), . -> next (group navigation). compatible: "m5stack,cardputer-keyboard" properties: pins-output: type: phandle-array element-type: "struct GpioPinSpec" required: true description: 3 GPIO pins driving the binary-encoded column-select lines, in scan-bit order pins-input: type: phandle-array element-type: "struct GpioPinSpec" required: true description: 7 GPIO pins reading the row lines, in scan-bit order