Specifications

AT Command Set Reference
Ver. 1.00
GSM1308AT001 Page 236 Ver. 1.00 – 10/29/2008
4.4.6. $IOPULUP GPIO Pullup Settings
Command Function This command allows the user to set the 20
GPIOs pullup state
Command Functional Enfora Specific
Group
Command Format Query AT$IOPULUP=?
Response $ IOPULUP: (20 0s – 20 1s)
OK
Write Format AT$ IOPULUP =<pullup_state>
Response OK
Read Format AT$ IOPULUP?
Response $ IOPULUP: < pullup_state >
OK
Execution Format N/A
Response N/A
Parameter Values
< pullup_state > 0 => pulldown.
1 => pullup.
Reference N/A
Standard Scope Optional
Enfora Implementation Scope Full
Notes 20 Digits where left bit represents GPIO 1
and right most bit represents GPIO 20.
GPIO 2 does not support the pullup feature
and will always be displayed as ‘x’ on a
query. GPIOs 3,13,14,15 can only be used
as pulldowns. GPIOs 9,10,11,12, and 18
are pullups only. GPIOs 1,4,5,6,
7,8,16,17,19, and 20 can function as either
pullups or pulldowns.