USR-GM3/GM3s User Manual
Jinan USR IOT Technology Limited
36 / 55
Type
Type
Type
Type of
of
of
of command
command
command
command
type
type
type
type
Command
Command
Command
Command string
string
string
string
description
description
description
description
0
AT+{CMD}?{CR}
query parameters
1
AT+{CMD}=?{CR}
Query the value of parameter
2
AT+{CMD}{CR}
execute action or query parameters
3
AT+{CMD}={PARAM}{CR}
Set the value of parameter
2)
2)
2)
2) The
The
The
The format
format
format
format of
of
of
of answering
answering
answering
answering
There are two kinds of response, with or without echo.
All the followings are using without echo as examples.
Command
Command
Command
Command string:
string:
string:
string: [CR][LF][+CMD][OP][PARA][CR][LF]<CR><LF>[OK]<CR><LF>
[CR][LF][+CMD][OP][PARA][CR][LF]<CR><LF>[OK]<CR><LF>
[CR][LF][+CMD][OP][PARA][CR][LF]<CR><LF>[OK]<CR><LF>
[CR][LF][+CMD][OP][PARA][CR][LF]<CR><LF>[OK]<CR><LF>
Type
Type
Type
Type of
of
of
of command
command
command
command
type
type
type
type
Command
Command
Command
Command string
string
string
string
description
description
description
description
0
<CR><LF><OK><CR><LF>
successful
1
<CR><LF><+CMD:><PARA><CR><LF><CR><LF><OK><CR><LF>
return parameter
Code
Code
Code
Code
meaning
meaning
meaning
meaning
necessary
necessary
necessary
necessary
AT+
AT command head
Yes
CMD
purpose of command
Yes
OP
action type of command
No
PARA
parameters of command
No
CR
termination of command
Yes
Code
Code
Code
Code
meaning
meaning
meaning
meaning
necessary
necessary
necessary
necessary
CR
carriage return
No
LF
line feed
No
+CMD
response head
No
OP
operator
No
PARA
parameter
No
CR
carriage return
No
LF
line feed
No
CR
carriage return
Yes
LF
line feed
Yes
OK
operating successful
No
CR
carriage return
Yes
LF
line feed
Yes
