There are two major types of commands: GET and SET commands. GET commands are used to receive information from Pearl - such as notifying the status or reading off a value. The SET command is for executing a change on Pearl itself.
In order to utilize an HTTP API command for changing layouts you will need to use a “set” configuration command, as well as the API key and the value of the layout
the set command would be:
http://< address >/admin/channel< N >/ set_params.cgi ?key= value
the key command in this case is for layout switching:
the value is the layout itself (such as layout 14)
example of command, assuming Channel 1 (of logical channel number) and layout 14. Example IP address of 192.168.2.404
You can find a list of key commands here for additional configuration and use