Telit Wireless Solutions GE910 - Page 51

GE910 Hardware User Guide
1vv0300962 Rev.12 2013-10-22
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved
page 51 of 83
Mod. 0805 2011-07 Rev.2
The signals of the GE910 Serial Port are:
RS232
Pin
Number
Signal GE910
Pad
Number
Name Usage
1 DCD - dcd_uart N14 Data Carrier Detect
Output from the GE910 that indicates
the carrier presence
2 RXD - tx_uart M15
Transmit line *see
Note
Output transmit line of GE910 UART
3 TXD -rx_uart N15 Receive line *see Note
Input receive of the GE910 UART
4 DTR - dtr_uart M14 Data Terminal Ready
Input to the GE910 that controls the
DTE READY condition
5 GND P13 Ground Ground
6 DSR - dsr_uart P14 Data Set Ready
Output from the GE910 that indicates
the module is ready
7 RTS -rts_uart L14 Request to Send
Input to the GE910 that controls the
Hardware flow control
8 CTS - cts_uart P15 Clear to Send
Output from the GE910 that controls
the Hardware flow control
9 RI - ri_uart R14 Ring Indicator
Output from the GE910 that indicates
the incoming call condition
NOTE:
According to V.24, RX/TX signal names are referred to the application side, therefore on the
GE910 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 GE910 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:
DTR pin should be disconnected before activating the Power Saving Mode.
NOTE:
In order to avoid a back powering effect it is recommended to avoid having HIGH logic level
signal applied to digital pins of the module when powered off or during an ON/OFF transition.