Panasonic TDA-600, Service Manual

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7 OUTLINE
7.1. GENERAL DESCRIPTION
The control system of this unit is composed of the main control section (EMPR) controlling the entire system, exchanging voice
data, the circuit control section (LPR) controlling various telephone lines, connecting bus lines between basic shelf and
expansion shelf (BUS-M) and the power supply section (POWER).
EMPR, LPR, BUS-M and POWER are connected to each other through the System BUS (ADDRESS BUS, DATA BUS and
CONTROL BUS). LPRs are under the I/O control (I/O Read/Write) of EMPR.
EMPR controls LPR which has a microprocessor by the lnter-Microprocessor Communication System supported by ASIC. That
is, EMPR and LPR exchange controlling messages through bi-directional buffer and CPU controls LPR so that it can manage
multiple telephone lines.
I/O address for LPR access is fixed per each free slot. CPU discriminates the sort of LPR through the inter-processor
communication system.
POWER detects the voltage drop of the AC input and the DC output and transfers it to EMPR.
7.1.1. EMPR Card
This card is the main control section of this unit. It controls all the cards mounted on the free slots, and communication of RS-
232C ports.
The front of the EMPR card is equipped with two LEDs (LED1 and LED2) that indicate the operating status of this card, slide
switches used to decide a system operation mode, and a push switch used to execute the system reset.
This control circuit executes the control signals for the exchange process, and this card is composed of the following
(A) 32bit CPU (32bit data bus)
(B) SDRAMs, SRAMs
(C) Flash memorys
(D) Lithium Battery for back-up of clock IC and Static RAMs
7.1.2. Back Board
BB (back board) is the mother board of the basic shelf. This board connects each card (POWER, EMPR, BUS-M and optional
cards) together. This board has one RS-232C connector.
7.1.3. Power Supply Unit
This unit is switching regulator power supply and supplies DC voltages to EMPR card, optional card (free slot).
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KX-TDA600CE