The keyboard controller (Figure 7) is a 12 button calculator-type switch array that functions like a small computer keyboard. When one of the pushbuttons is pressed, the corresponding set of sense lines is closed, completing the circuit. The closure is detected by the 6532 and appropriate action is taken by the program. Figure 8 illustrates the keyboard controller wiring diagram and Figure 9 the keyboard schematic.
FIGURE 7. KEYBOARD CONTROLLER ASSEMBLY (EXPANDED VIEW)
FIGURE 8. KEYBOARD CONTROLLER WIRING DIAGRAM
FIGURE 9. KEYBOARD CONTROLLER SCHEMATIC (WITH PINOUTS)
KEYBOARD CONTROLLER CHECK
Known good VCS unit
Brain Games cartridge
One good keyboard controller
- Check for cosmetic damage.
- Plug in Brain Games cartridge and plug the known good keyboard into the right-hand plug.
- Plug the controller to be tested into the left-hand plug.
- Press game select until game II 19 appears and press game reset.
- If an audio tone sounds, the controller is defective.
- Starting with the "I" key, press the keys in the following order: 1, 2, 3, 4, 5, 6, 7, S, 9, *, 0, #. Each key should generate a tone lower than the key before it.
- Test completed.