1. Overview:
This instruction is for how to use Peer to Peer firmware in LA66.
2. Firmware Location:
Click here to download the firmware and update it to LA66 according to the instruction for different boards.
3. How to use?
3.1 AT command：
1). Lora parameter configuration:
AT+FRE: Get or Set TX and RX frequency
AT+BW: Get or Set TX and RX BandWidth
AT+SF: Get or Set TX and RX Spreading Factor
AT+POWER: Get or Set Tx Power Range
AT+CRC: Get or Set TX and RX CRC Type
AT+HEADER: Get or Set TX and RX Header Type
AT+CR: Get or Set TX and RX Header Type
AT+IQ: Get or Set TX and RX InvertIQ
AT+PREAMBLE: Get or Set TX and RX Preamble Length
AT+SYNCWORD: Get or Set sync word
2). General configuration:
ATZ: Trig a reset of the MCU
AT+FDR: Reset Parameters to Factory Default
AT+CFG: Print all configurations
AT+FCU: Get or Set the Frame Counter Uplink
AT+FCD: Get or Set the Frame Counter Downlink
AT+GROUPMOD: Get or Set TX and RX group
AT+RXMOD: Get or Set Rx Timeout and Reply mode
AT+SEND: Send text data or hex along with the application port and confirm status
AT+RECV: Print last receive message, RSSI and SNR
3.2 Serial port information
1). Information initialized at reset：
2). In retransmission, the Uplinkcounter does not accumulate. The following figure shows that the third count packet is retransmitted twice when the ACK packet is not received.
3). In the figure below, the receiver sends an ACK to the sender after receiving the packet, and the sender stops retransmission after receiving the ACK.
Receiver: (configured as AT+RXMOD=65535,2)
Sender:
3.3 Data Format:
1 byte of TXGROUPMOD +n payload + 4 bytes of checksum
Payload(S12, SF11, SF10 maximum length is 59, SF9 maximum length is 123, SF8, SF7 maximum length is 230):
| Size (bytes) | 1 | payloadsize |
|---|---|---|
| Value | TXGroupmod | Send data |
4. AT Command Set:
4.1 Set TX and RX Bandwidth
Set TX and RX BandWidth (0 ~ 9):
0: 125 kHz
1: 250 kHz
2: 500 kHz
3: 62.5 kHz
4: 41.67 kHz
5: 31.25 kHz
6: 20.83 kHz
7: 15.63 kHz
8: 10.42 kHz
9: 7.81 kHz
Default Value: AT+BW=0,0 // BandWidth: 125kHz ,125kHz
Range: (0 ~ 9)