1. Features
 8bits micro-controller with Pipe-line structured 8051 compatible instruction set
 Flash ROM: 16K Bytes
 RAM: internal 256 Bytes, external 1280 Bytes
 Operation Voltage: 2.7V - 5.5V
 Oscillator:
- Internal RC: 27MHz (±2%)
- External crystal oscillator: 32.768kHz
 28pin: 25 CMOS bi-directional I/O pins
20pin: 17 CMOS bi-directional I/O pins
 Built-in pull-up resistor for input pin
 Three 16-bit timer/counters T2, T3 & T4
 20 channels Touch Key input
 Built-in Touch Key comparison voltage:
1V, 1.5V, 2V, 2.5V
 7 COM 16 SEG LED drive
 Touch Key sharing with LED drive
 Powerful interrupt sources:
- Timer2, 3, 4
- INT0, INT1, INT2, INT4
- EUART
- Touch Key
- TWI
 EUART with Baud-rate generator
 TWI communication interface
 Built-in 2 channels programmable tone generator
 CPU Machine cycle: 1 oscillator cycle
 Watch Dog Timer (WDT)
 Flash Type
 Package: SOP28
SOP20
SOP16