Rainbow Electronics GM862-GPS User Manual
Page 36
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GM862-GPS Hardware User Guide
1vv0300728 Rev. 8 - 20/09/07
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved
page 36 of 73
The signals of the GM862-GPS MODEM serial port are:
RS232
Pin
Number
Signal
GM862-
GPS Pin
Number
Name
Usage
1
DCD -
dcd_uart
36
Data Carrier Detect
Output from the GM862-GPS that indicates the
carrier presence
2
RXD -
tx_uart
37
Transmit line *see Note
Output transmit line of GM862-GPS UART
3
TXD -
rx_uart
20
Receive line *see Note
Input receive of the GM862-GPS UART
4
DTR -
dtr_uart
43
Data Terminal Ready
Input to the GM862-GPS that controls the DTE
READY condition
5
GND
2-4
Ground
Ground
6
DSR -
dsr_uart
33
Data Set Ready
Output from the GM862-GPS that indicates the
module is ready
7
RTS -
rts_uart
45
Request to Send
Input to the GM862-GPS that controls the
Hardware flow control
8
CTS -
cts_uart
29
Clear to Send
Output from the GM862-GPS that controls the
Hardware flow control
9
RI - ri_uart
30
Ring Indicator
Output from the GM862-GPS that indicates the
incoming call condition
NOTE: According to V.24, RX/TX signal names are referred to the application side, therefore on the GM862-GPS side
these signal are on the opposite direction: TXD on the application side will be connected to the receive line (here
named TXD/ rx_uart ) of the GM862-GPS serial port and viceversa for RX.
TIP: For a minimum implementation, only the TXD and RXD lines can be connected, the other lines can be left open
provided a software flow control is implemented.