Cinterion
®
LTE Terminals Hardware Interface Description
8.3 Complete Watchdog Configuration
101
ELSxT_HID_v04
2018-09-04
Confidential / Preliminary
Page 84 of 102
8.3.1.11
Set GPIO Direction
This command configures the input/output direction of level-shifters to the module‘s externally
available GPIO pins. The argument is a 10-bit number, representing the 10 adjustable direc-
tions of the GPIO level-shifters. A set bit (value 1) sets the respective level-shifter to the output
direction. A cleared bit changes the respective level-shifter to input direction. The following ta-
ble describes the connection between the 10-bit argument number, the modules GPIO pins,
and the LTE Terminals GPIO connectors 8-pin and 12-pin:
Changing the directions of the level-shifters must be executed with great care. They may only
be set in accordance with the LTE modules‘ GPIO input/output configuration. Special care must
be taken that no outputs are cross-connected during the switching phase.
Configuring a LTE Terminal output, the level shifter output should be set first, followed by the
module output configuration. Configuring an input, the module input should be set first, followed
by the level shifter input. Please refer to
for more information on how to configure
GPIO directions.
Please note that the GPIO direction can also be configured via I
2
C interface (see
).
It is recommended to use the I
2
C interface to configure the GPIO direction.
Note: Not every GPIO is supported by every LTE Terminal variant - see
Command
GPIO_DIR
Parameter
<pin-config>
Type
Number
Range
0-1023
Default
0 (0x000, 0000000000b)
Non-volatile
Yes
Example
WD= GPIO_DIR,682,16
// Sets the GPIOs alternating to output and input
(binary value: 1010101010b)
10-Bit number
GPIO
8-pin connector
12-pin connector
Default
0
GPIO6
1
-
Input
1
GPIO7
2
-
Input
2
GPIO8
3
-
Input
3
GPIO11
4
-
Input
4
GPIO12
5
-
Input
5
GPIO13
6
-
Input
6
GPIO22
7
-
Input
7
GPIO23
8
-
Input
8
GPIO21
-
12
Input
9
GPIO20
-
11
Input