User's Manual

GE866-DUAL Hardware User Guide
1VV0301051 Rev. 2 – 2014-04-07 7
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Reserved. Page 44 of 82
Mod. 0805 2011-07 Rev.2
Input high level V
IH
1.5V 1.9V
Input low level V
IL
0V 0.35V
Output high level V
OH
1.6V 1.9V
Output low level V
OL
0V 0.2V
The signals of the GE866-QUAD serial port are:
RS232 Pin
Number
Signal GE866-QUAD
Pad Number
Name Usage
1 DCD - dcd_uart B2 Data Carrier Detect
Output from the
GE866
-
QUAD
that
indicates the carrier presence
2 RXD - tx_uart A5
Transmit line *see
Note
Output transmit line of GE866-
QUAD UART
3 TXD - rx_uart A4 Receive line *see Note
Input receive of the
GE866
-
QUAD
UART
4 DTR - dtr_uart A2 Data Terminal Ready
Input to the GE866-QUAD that
controls the DTE READY condition
5 GND
D1, F1, G1, D2,
F2, C2, E3, F3,
G3
Ground Ground
6 DSR - dsr_uart A3 Data Set Ready
Output from the GE866-QUAD that
indicates the module is ready
7 RTS - rts_uart A1 Request to Send
Input to the
GE866
-
QUAD
that
controls the Hardware flow control
8 CTS - cts_uart B1 Clear to Send
Output from the GE866-QUAD that
controls the Hardware flow control
9 RI - ri_uart B3 Ring Indicator
Output from the
GE866
-
QUAD
that
indicates the incoming call condition
NOTE:
According to V.24, RX/TX signal names are referred to the
application side, therefore on the GE866-QUAD 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 GE866-QUAD serial port and vice versa 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: