User's Manual

GL865-DUAL/QUAD V3 Hardware User Guide
1vv0301018 Rev.7 – 2013-10-30
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights
Reserved. Page 39 of 78
Mod. 0805 2011-07 Rev.2
The signals of the GL865-DUAL/QUAD V3 serial port are:
RS232 Pin
Number
Signal GL865-
DUAL/QUAD V3
Pad Number
Name Usage
1 DCD - dcd_uart 1 Data Carrier Detect
Output from the GL865-DUAL/QUAD
V3 that indicates the carrier presence
2 RXD - tx_uart 8 Transmit line *see Note
Output transmit line of GL865-
DUAL/QUAD V3 UART
3 TXD - rx_uart 7 Receive line *see Note
Input receive of the GL865-
DUAL/QUAD V3
UART
4 DTR - dtr_uart 4 Data Terminal Ready
Input to the GL865-DUAL/QUAD V3
that controls the DTE READY condition
5 GND 32, 33, 35, 36, 46 Ground Ground
6 DSR - dsr_uart 3 Data Set Ready
Output from the GL865-DUAL/QUAD
V3 that indicates the module is ready
7 RTS -rts_uart 5 Request to Send
Input to the GL865-DUAL/QUAD V3
that controls the Hardware flow control
8 CTS - cts_uart 6 Clear to Send
Output from the GL865-DUAL/QUAD
V3 that controls the Hardware flow
control
9 RI - ri_uart 2 Ring Indicator
Output from the GL865-DUAL/QUAD
V3 that indicates the incoming call
condition
NOTE:
According to V.24, RX/TX signal names are referred to the application side, therefore on the
GL865-DUAL/QUAD V3 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
GL865-DUAL/QUAD V3 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:
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 GL865-DUAL/QUAD V3 when the module is
powered off or during an ON/OFF transition.