GENERAL DESCRIPTION

The EM78811 is an 8-bit CID (Call Identification) RISC type microprocessor with low power , high speed CMOS technology. Integrated onto a single chip are on_chip watchdog (WDT) , RAM , ROM , programmable real time clock /counter , internal interrupt , power down mode , LCD driver , FSK decoder , DTMF generator and tri-state I/O . The EM78811 provides a single chip solution to design a CID of calling message_display .

FEATURES

CPU

• Operating voltage range : 2.5V~5.5V

• 16K X13 on chip ROM

• 2.8K X 8 on chip RAM

• Up to 32 bi-directional tri-state I/O ports

• 8 level stack for subroutine nesting

• 8-bit real time clock/counter (TCC)

• Two sets of 8 bit counters can be interrupt sources

• Selective signal sources and trigger edges , and with overflow interrupt

• Programmable free running on chip watchdog timer

• 99.9 single instruction cycle commands

• Three modes (internal clock 3.679MHz)

1. sleep mode : CPU and 3.679MHz clock turn off, 32.768KHz clock turn off

2. Idle mode : CPU and 3.679 MHz clock turn off, 32.768KHz clock turn on

3. Green mode : 3.679MHz clock turn off, CPU and 32.768KHz clock turn on

4. Normal mode : 3.679MHz clock turn on , CPU and 32.768KHz clock turn on

• Ring on voltage detector and low battery detector

• Input port wake up function

• 8 interrupt source , 4 external , 4 internal

• 100 QFP or chip

• Port key scan function

• Port interrupt, Pull high and Open drain functions

• Clock frequency 32.768KHz

• Main clock can switch to 1.84MHz by code option

CID

• Operation Volltage 3.5 ~5.5V for FSK

• Operation Volltage 2.5 ~5.5V for DTMF

• Bell 202 , V.23 FSK demodulator

• DTMF generator

• Ring detector on chip

LCD

• LCD operation voltage chosen by software

• Common driver pins : 16

• Segment driver pins : 60

• 1/4 bias

• 1/8,1/16 duty

APPLICATION

1. adjunct units

2. answering machines

3. feature phones