Control Circuit - Panasonic KX-TES824LA Service Manual

KX-TES824LA / KX-TEM824LA /

11.7. CONTROL CIRCUIT

11.7.1. Composition
The control block is composed of the 16bit CPU(IC700: operating on 23.966MHz system clock from the 47.936MHz external crystal
oscillator), the 8Mbit Flash ROM, the 4Mbit SRAM, and the ASIC for the I/O Port to control the outside line.
The port to control the extension, the clock IC, the address decoder, and other CPU Peripheral circuit are included in the
IC700.Also, the IC700 includes functions such as Extension CID(FSK, DTMF), MODEM sending/receiving, BGM, OGM
recording/playing, DTMF tone, CNG tone, CPT tone, and VOX detection.
The SRAM has a lithium battery to back up information such as speed dial, date, dial data, and system data etc. The battery also
backs up the clock IC in the IC700.
I/O Port to control extension circuit, clock IC, address decoder, and other CPU Peripheral function are included in IC700. And IC700
include the functions as transmission of Extension Caller ID, transmission & receive of MODEM, transmission BGM, recording &
playing of OGM, detect of DTMF tone, CNG tone, CPT tone & VOX.
the SRAM has a lithium battery as back up for protection of the memory of information of such as the speed dial, date, dial data,
and system data, etc. This battery is back up clock IC in IC700 too.
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