5. Appendix
5.1. AT Commands
5.1.1. AT Command Basics
There are four types of commands you can issue to the modem. The four types are described in
the table below. Not all AT commands will have every type of command available (test, read,
write, execute). This will make more sense after reviewing the table below.
Type
Syntax
Function
Test
Command
AT+<x>=?
Returns a list of acceptable values the user can assign to the
parameter, i.e. values that are okay to use with the
Write Command
.
Read
Command
AT+<x>?
Returns the currently set value of the parameter.
Write
Command
AT+<x>=<...>
Sets the parameter to the value defined by the user’s entry.
Execution
Command
AT+<x>
Returns the value of a non-variable parameter. This type of parameter
is affected by internal processes of the modem. A non-variable
parameter cannot be changed with a user entry.
Variable Parameter Example
:
The
"
CFUN
"
parameter was selected to demonstrate the
different types of commands for a variable parameter.
Type
Syntax
Description
Test
Command
AT+<x>=?
Command
:
AT+CFUN=?
Response
:
+CFUN: (0,1,4),(0,1)
Tells you that the first parameter may be set to 0, 1, or 4 and the
second to 0 or 1.
Read
Command
AT+<x>?
Command
:
AT+CFUN?
Response
:
+CFUN: 1
Tells you that CFUN is currently set to 1, meaning that the modem is
set in full functionality mode.
Write
AT+<x>=<...>
Command
:
AT+CFUN=4
PN 1002152 REV A
© NimbeLink Corp. 2019. All rights reserved.
29
