Service manual

Service Manual SD170E Series
Page 32 of 44
10
CMD_IN/OUT
Data Input and Output for Modem programming.
I/P,
O/P
11
CMD_CLK
Clock Input for Modem programming.
I/P
12
MODEM_SEL
It Indicates modem type to Master MCU for
programming.
O/P
13
RX_IN
The GMSK signal input for the receiver of
modem IC.
I/P
14
TX_OUT
The GMSK filtered TX output signal.
O/P
Connector
2
1
Serial_IN
The Serial data to be transmitted is input to this
pin.
I/P
2
Serial_OUT
The recovered asynchronous serial data output
from the receiver.
O/P
3
Busy
To eliminate data loss according to buffer
overrun of slave MCU‟s memory, it indicates
buffer status.
O/P
4
Carrier Detect
Handshake signal for RTS control mode. It
indicates whether Slave MCU of modem has
decoded data or not.
O/P
5
PTT_IN
Handshake signal for RTS control mode. It
requests data transmission to Slave MCU of
modem.
I/P
6
PROGRAM
It‟s reserved input for firmware upgrade.
I/P
ACC-514 (FFSK Modem Option board)
Connector
No.
Pin
No.
Function
Description
Input/
Outp
ut
Connector
1
1
VCC
6V to 12V Power Input
I/P
2
GND
Ground
3
PTT
Signal from the digital board to transmit data key
the SD-160 transmitter
I/P
4
TXD_EN
It ensures that the radio has stabilized in
transmission before the data is processed for
modulation.
I/P
5
TX_END
To finish transmission, it indicates memory buffer of
Master MCU of digital board is empty.
O/P
6
MUTE
(Busy)
Logic level input from digital board to indicate
whether a carrier is present or not
I/P
7
MODEM_EN
Modem Enable input
I/P
8
POWER_SA
VE
Power save input for modem board.
I/P