Hardware Guide

GE865 Hardware User Guide
1vv0300799 Rev.15– 2012-04-23
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The signals of the GE865 serial port are:
RS232
Pin
Number
Signal
GE865
Pad Number
Name
Usage
1 DCD - dcd_uart B5 Data Carrier Detect
Output from the GE865 that indicates the
carrier presence
2
RXD -
tx_uart
A4 Transmit line *see Note Output transmit line of GE865 UART
3
TXD -
rx_uart
A3 Receive line *see Note Input receive of the GE865 UART
4 DTR - dtr_uart B3 Data Terminal Ready
Input to the GE865 that controls the DTE
READY condition
5 GND
C2, C7, E5,
E7, G1, G3,
G4, G5, H3,
H6
Ground ground
6 DSR - dsr_uart B2 Data Set Ready
Output from the GE865 that indicates the
module is ready
7 RTS -rts_uart A1 Request to Send
Input to the GE865 that controls the
Hardware flow control
8 CTS - cts_uart A2 Clear to Send
Output from the GE865 that controls the
Hardware flow control
9 RI - ri_uart B4 Ring Indicator
Output from the GE865 that indicates the
incoming call condition
NOTE:
According to V.24, RX/TX signal names are referred to the application side, therefore on the
GE865 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 GE865 serial port and
viceversa for RX.
NOTE:
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.
NOTE:
In order to avoid a back powering effect it is recommended to avoid having any HIGH logic
level signal applied to the digital pins of the GE865 when the module is powered off or during
an ON/OFF transition.