All MQTT functionalities of the P4M-440G are executed through AT commands. Therefore, it is essential for users to be familiar with the usage of AT commands.
AT commands and responses are composed of ASCII strings and are case-insensitive. Every AT command always starts with 'AT' and ends with '<CR>'.
※ <CR>: Carriage Return, 0x0d
| Command | Description | Usage |
|---|---|---|
| E | Command Echo OFF/ON | OFF: ATE0<CR>, ON: ATE1<CR> |
| Z | Reset & Reboot | ATZ<CR> |
| Command | Description |
|---|---|
| +MCT | Setting Timeout |
| +MCCF | Setting Connection Flags |
| +MCCP | Setting Connection Payload |
| +MCB | Setting QoS |
| +MNC | Connecting to a Broker |
| +MND | Disconnecting from a Broker |
| +MNG | Reading Messages |
| +MBT | Setting Topic Buffer |
| +MBM | Setting Message Buffer |
| +MBP | PUBLISH |
| +MBS | SUBSCRIBE |
| +MBU | UNSUBSCRIBE |
| +MQNS | Getting Status |
| +MQNU | Getting the number of unread messages |
| +MQNR | Getting the size of a received message |
| +MQC | Getting the client ID |
| +MCO | Setting the short response mode |
| Response | Description |
|---|---|
| OK | get ready or a command executed successfully |
| ERROR | a command executed error |
| otherwise | a response corresponding to each command |