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PneumADDic II • Masterpiece 4 223
Keyboard Column Sensor Step 5

Only one of the four
touch sensors is ever
pressed at a time. The RCX can
tell which of the four touch sensors
was pressed because the resistor blocks
force different analog voltage readings at the
RCX sensor input for different touch sensors.

Left Keyboard Buttons

The Left Keyboard Buttons sub-assembly contains two touch sensors.

Left Keyboard Buttons Step 0