Kenwood TS-2000, Руководство по обслуживанию

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22
TS-2000/X
Digital Control Circuit
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Outline
The TS-2000/X control circuit has a multi-chip configura-
tion centered around a main microcomputer (IC8), and con-
tains a latch circuit for input/ output, a TNC and a DSP. Refer
to the digital control block diagram.
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Main microcomputer peripherals
Four serial communication devices utilizing a UART func-
tion (panel microcomputer, TNC, mobile head and PC serial
port) are connected to the main microcomputer. An
EEPROM (IC7) for backup and a DTMF decoder (IC12) for
DTMF signal detection are also connected to the microcom-
puter.
The input/output circuit and DSP are connected through
an address bus and a data bus. The bus to the DSP is con-
nected through 5V
↔
3V voltage conversion ICs (IC9, IC10,
and IC11)
The microcomputer operates with an internal core volt-
age of 3.3V, an external I/O voltage of 5V and an internal
frequency of 22.1184MHz (11.0592MHz x 2).
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TNC
The TNC is the same as the one used in the TH-D7. The
TNC uses a lithium battery to back up various settings.
When a 9600bps communication speed is used, the TNC
analog signal is connected directly to the transmitter/re-
ceiver circuit without passing through the DSP.
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Input/output latch circuit
A latch IC is used in stead of several input/output ports.
Since the latch IC has a latch function only, the latch circuit
contains an input latch logic circuit (IC13, IC14, IC15) and an
output latch logic circuit (IC16, IC17, IC18) to generate the
s i g n a l s r e q u i r e d f o r t h e l a t c h I C u s i n g t h e m a i n
microcomputer’s address bus information. This configura-
tion is also used for the latch IC of the DSP section.
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Other peripheral circuits
The main microcomputer is connected with other periph-
eral circuits, such as a reset circuit that generates a reset
signal, a reduced voltage detection circuit that detects re-
duced voltage and generates a reduced voltage signal, and
an over-voltage detection circuit that detects over-voltage
and generates an over-voltage signal.
DSP1 address bus (3V)
Main
microcomputer
IC8
2 Chip TNC
(by TASCO)
DTMF decoder
LC73881
IC12
PC (RS-232C)
Latch IC for output
TC74VHC573FT
IC21~IC25
Latch IC for output
TC74VHC573FT
IC505,IC506
Reset circuit
Over voltage
detection circuit
Latch IC for input
TC74VHC573FT
IC19,IC20
Latch IC for input
TC74VHC573FT
IC512,IC514
Data bus (5V)
Address bus (5V)
DSP1 data bus (3V)
Logic circuit
for input latch
IC13~IC15
Logic circuit
for input latch
IC509~IC511,IC513
CODEC IC
AK4518
IC522
EEPROM
ATMEL
AT25128N
IC7
Address bus (3V)
Data bus (3V)
DSP2 address bus (3V)
DSP2 (IF DSP)
TMS320VC5402PGE
IC515
CODEC IC
AK4524
IC518
FLASH ROM
IC504
DSP2 data bus (3V)
RIF
Control (X53-391)
SDET
TIF
AGC
MA
SA
MANO
SANO
MIC/DRU
VS-3
Over voltage
detection circuit
FLASH ROM
IC508
DSP1 (AF DSP)
TMS320VC5402PGE
IC516
CODEC IC
AK4518
IC523
Panel micro-
computer
Mobile
head
Conversion
from 5V to 3V
IC10,IC11
Conversion
between 5V and 3V
IC9
Logic circuit
for output latch
IC16~IC18
Logic circuit
for output latch
IC507
Input port
Input port
Output port
Output port
Fig. 19 Digital control block diagram
CIRCUIT DESCRIPTION