Gemalto Cinterion ELS31T-J, Hardware Interface Description, Page: 32 / 102

Cinterion
®
LTE Terminals Hardware Interface Description
3.6 GPIO Interface
47

ELSxT_HID_v04 2018-09-04
Confidential / Preliminary
Page 32 of 102
Please refer to the respective “AT Command Set“ for details on how to configure the GPIO pins
using AT commands.
Also, be sure not to activate SLEEP mode, e.g., by setting AT^SPOW with <mode>=2, for the
ELS61 module, as the module may no longer be able to wake up from SLEEP mode, and will
then have to be reset.
3.6.1 Serial Interface ASC1
On all LTE Terminals four pins at the GPIO connector can be configured as ASC1 interface
signals to provide a 4-wire serial modem interface ASC1. For electrical characteristics please
refer to
Table 23 .
The following pins at the GPIO connector can be configured as ASC1 interface signals: RXD1,
TXD1, RTS1 and CTS1 (see also
Table 14 ). The configuration is done by AT command
AT^SCFG - see [1] . It is non-volatile and becomes active after a LTE Terminal restart.
LTE Terminals are designed for use as a DCE. Based on the conventions for DCE-DTE con-
nections they communicate with the customer application (DTE) using the following signals:
•
Port TXD @ application sends data to LTE Terminal’s TXD1 signal line
• Port RXD @ application receives data from the LTE Terminal’s RXD1 signal line
Hardware handshake using the RTS1 and CTS1 signals is supported on all LTE Terminals.
2 GND     
3 TXD1 or
SPI_MISO
Configurable via AT command,
also as SPI_MISO signal
TXD1 /
SPI_MISO
TXD1 /
SPI_MISO
TXD1 /
SPI_MISO
TXD1 /
SPI_MISO
TXD1
4 RXD1 or
SPI_MOSI
Configurable via AT command,
also as SPI_MOSI signal
RXD1 /
SPI_MOSI
RXD1 /
SPI_MOSI
RXD1 /
SPI_MOSI
RXD1 /
SPI_MOSI
RXD1
5 CTS1 or
SPI_CS
CTS1 (RS-232) or
SPI_CS
CTS1 /
SPI_CS
CTS1 /
SPI_CS
CTS1 /
SPI_CS
CTS1 /
SPI_CS
CTS1
6 RTS1 RTS1 (RS-232) RTS1 RTS1 RTS1 RTS1 RTS1
7 +5Vout External power supply up to
100mA, usable as VCCref input
    
8 DSR0 or
ADC1_IN
or SPI_CLK
Configurable via AT command     DSR0 /
ADC1_IN
9 I2CDAT I
2
C interface     
10 I2CCLK I
2
C interface     
11 GPIO20 Configurable via AT command
also as DOUT

no DAI

no DAI

no DAI

DOUT

no DAI
12 GPIO21 Configurable via AT command
also as DIN

no DAI

no DAI 

no DAI

DIN

no DAI
Table 14:
GPIO connector pin availability and alternate pin functionalities
PI
N Signal Comment ELS61T-
US ELS61T-
AUS ELS61T-
E ELS61T-
E2 ELS31
T-V/J