Cermetek Microelectronics, Inc Page 25 of 42
Document NO. 607-00xx Revision A (12/13)
4 AT+ COMMANDS
4.1 Configuration Mode
When the CH232BGN is powered up, it defaults to transparent transmission mode. The user can
change the configuration through the serial port using AT+ commands. The default UART settings are
shown in Figure 24 below.
Figure 3 CH232BGN Default UART Port Parameters
There are two steps to switch from transparent transmission mode to configuration mode.
Step 1:
Send the text string
“+++” to the CH232BGN. The module responds with “a” to confirm receipt
of the command.
Step 2:
Send
the character “a” to the CH232BGN. The CH232BGN responds with “+ok” and enters
AT+ configuration mode.
Notes: The
”+++” character string is not echoed back to the serial port.
If the CH232BGN receives any input other
than the “+++”, the module continues to operate in
transparent transmission mode.
4.2 AT+ Command Set Overview
All configuration of the CH232BGN can be accomplished by issuing AT+ commands through the
module’s serial port. Descriptions of the AT+ commands follow.
4.2.1
Document Format
Below is a list of the conventions used in this document to describe the AT+ commands
< >
: Text shown between the less-than sign and greater-than sign is required.
[ ]
: Text shown within the brackets is optional.
