General Description
The EM78910/910A is an 8-bit CID (Call Identification) RISC type microprocessor with low power, high speed CMOS technology. This integrated single chip has on_chip watchdog (WDT), RAM, ROM, programmable real time clock/counter, internal interrupt, power down mode, FSK decoder, Call waiting decoder, SDT (Stuttered dial tone) decoder, DTMF generator, MEI (Multiple Extension Internetworking) function, RTF (Request To Flash) function and tri-state I/O. The EM78910/910A provides a single chip solution to design a CID of calling message_display.

Feature
CPU
• Operating voltage range : 2.5V〜5.5V
• 16K × 13 Read Only Memory
• 1.1K× 8 on chip RAM
• Up to 28 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
• Four modes (Main clock 3.579MHz or 1.79MHz)
• Ring on voltage detector
• Universal Low battery detector
• Input port wake up function
• 9 interrupt source , 4 external , 5 internal
• Port key scan function
• Clock frequency 32.768KHz
• Eight R-option pins

CID
• Bell 202 , V.23 FSK demodulator
• DTMF generator
• Ring detector on chip

CALL WAITING
• Compatible with Bellcore special report SR-TSV-002476
• Call-Waiting (2130Hz plus 2750Hz) alert signal detection
• Good talkdown and talkoff performance
• Sensitivity compensated by adjusting input OP gain

SDT
• Stuttered Dial Tone (350Hz plus 440Hz) signal detection

MEI/RTF
• Compatible with TIA/EIA-777(TIA SP-4078)
• MEI(Multiplex Extension Internetworking) and RTF(Request To Flash) functions

PACKAGE
• 45-pin die form without MEI/RTF (EM78910AH, POVD disable)(EM78910BH, POVD enable)
• 47-pin die form with MEI/RTF (EM78910AAH, POVD disable)(EM78910ABH, POVD enable)

Application
1. Adjunct units
2. Answering machines
3. Feature phones