4.2 Command Packets
The command packet is broken down as shown in Table 4-2:
| Byte | Name | Meaning |
|---|---|---|
| 0 | Opcode | The command code. See Section Device Commands . |
| 1 | Param1 | The first parameter; always present. |
| 2 – 3 | Param2 | The second parameter; always present. |
| 0 – 155 | Data | Optional remaining input data. |
After the ATECC608B-TNGLoRaWAN receives all the bytes in a group, the device transitions to the Busy state and attempts to execute the command. Neither status nor results can be read from the device when it is busy. During this time, the I/O interface of the device ignores all transitions on the I2C SDA input signal.