Installation guide

LMU Users Guide
V1.0.6 December 10 2009
Copyright ©CalAmp DataCom Inc 2009
- 18 - CalAmp Proprietary & Confidential
4.4
The input or output functionality of the GPIO pins is controlled by S-Register 159. Like the
input bias controls, each bit is associated with a different GPIO. If the bit is set, then the
GPIO will act as an output. If the bit is cleared, the GPIO will act as an input. The following
bit mappings are available:
Selecting the GPIO Function
Bit
Input
S-Register Mask
0
GPIO 1
1
1
GPIO 2
2
For example to set GPIO 1 as an output and GPIO 2 as an input you would use:
AT$APP PARAM 1024,39,1,1
AT$APP PARAM 1024,39,2,0
Or you could use the single command of
ATS157 = 1