Circuit Operation - Sony UP-21MD Service Manual

4-4-3. Circuit Operation
* Reset circuit
Pin74 | TP106:RESET3 Mechanical control block
* Oscillator circuit
The basic clock (9.8304 MHz) of the SY-299 board that is generated using an oscillator circuit
incorporating a crystal oscillator (X101) and CPU (IC103) can be confirmed at pin 61 of IC103.
* Nonvolatile memory
¢ Buzzer control
* Liquid-crystal display (LCD) contro!