EBYTE LoRa E22 devices raspberrypi library (SX1262, SX1268)

Changelog

• 2023-05-02 0.0.4 Fix message size error
• 2023-04-25 0.0.3 Minor fixes
• 2023-03-21 0.0.1 Fully functional library

Library usage

Here an example of constructor, you must pass the UART interface and (if you want, but It's reccomended) the AUX pin, M0 and M1.

Installation

To install the library execute the following command:

pip install ebyte-lora-e22-rpi

Initialization

from lora_e22 import LoRaE22
import serial

loraSerial = serial.Serial('/dev/serial0') #, baudrate=9600, parity=serial.PARITY_NONE, stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS)
lora = LoRaE22('400T22D', loraSerial, aux_pin=18, m0_pin=23, m1_pin=24)

Start the module transmission

code = lora.begin()
print("Initialization: {}", ResponseStatusCode.get_description(code))

Get Configuration

from lora_e22 import LoRaE22, print_configuration
from lora_e22_operation_constant import ResponseStatusCode

code, configuration = lora.get_configuration()

print("Retrieve configuration: {}", ResponseStatusCode.get_description(code))

print_configuration(configuration)

The result

# ----------------------------------------
# HEAD :  0xc1   0x0   0x9
#
# AddH :  0x0
# AddL :  0x0
#
# Chan :  23  ->  433
#
# SpeedParityBit :  0b0  ->  8N1 (Default)
# SpeedUARTDatte :  0b11  ->  9600bps (default)
# SpeedAirDataRate :  0b10  ->  2.4kbps (default)
#
# OptionSubPacketSett:  0b0  ->  240bytes (default)
# OptionTranPower :  0b0  ->  22dBm (Default)
# OptionRSSIAmbientNo:  0b0  ->  Disabled (default)
#
# TransModeWORPeriod :  0b11  ->  2000ms (default)
# TransModeTransContr:  0b0  ->  WOR Receiver (default)
# TransModeEnableLBT :  0b0  ->  Disabled (default)
# TransModeEnableRSSI:  0b0  ->  Disabled (default)
# TransModeEnabRepeat:  0b0  ->  Disabled (default)
# TransModeFixedTrans:  0b0  ->  Transparent transmission (default)
# ----------------------------------------

Set Configuration

You can set only the desidered parameter, the other will be set to default value.

configuration_to_set = Configuration('400T22D')
configuration_to_set.ADDL = 0x02
configuration_to_set.ADDH = 0x01
configuration_to_set.CHAN = 23

configuration_to_set.NETID = 0

configuration_to_set.SPED.airDataRate = AirDataRate.AIR_DATA_RATE_100_96
configuration_to_set.SPED.uartParity = UARTParity.MODE_00_8N1
configuration_to_set.SPED.uartBaudRate = UARTBaudRate.BPS_9600

configuration_to_set.OPTION.subPacketSetting = SubPacketSetting.SPS_064_10
configuration_to_set.OPTION.transmissionPower = TransmissionPower('400T22D').\
                                                    get_transmission_power().POWER_10
# or
# configuration_to_set.OPTION.transmissionPower = TransmissionPower22.POWER_10
configuration_to_set.OPTION.RSSIAmbientNoise = RssiAmbientNoiseEnable.RSSI_AMBIENT_NOISE_ENABLED

configuration_to_set.TRANSMISSION_MODE.WORTransceiverControl = WorTransceiverControl.WOR_TRANSMITTER
configuration_to_set.TRANSMISSION_MODE.enableLBT = LbtEnableByte.LBT_DISABLED
configuration_to_set.TRANSMISSION_MODE.enableRSSI = RssiEnableByte.RSSI_ENABLED
configuration_to_set.TRANSMISSION_MODE.enableRepeater = RepeaterModeEnableByte.REPEATER_DISABLED
configuration_to_set.TRANSMISSION_MODE.fixedTransmission = FixedTransmission.FIXED_TRANSMISSION
configuration_to_set.TRANSMISSION_MODE.WORPeriod = WorPeriod.WOR_1500_010

configuration_to_set.CRYPT.CRYPT_H = 1
configuration_to_set.CRYPT.CRYPT_L = 1


# Set the new configuration on the LoRa module and print the updated configuration to the console
code, confSetted = lora.set_configuration(configuration_to_set)

I create a CONSTANTS class for each parameter, here a list: AirDataRate, UARTBaudRate, UARTParity, TransmissionPower, ForwardErrorCorrectionSwitch, WirelessWakeUpTime, IODriveMode, FixedTransmission

Send string message

Here an example of send data, you can pass a string

lora.send_transparent_message('pippo')

lora.send_fixed_message(0, 2, 23, 'pippo')

Here the receiver code

while True:
    if lora.available() > 0:
        code, value = lora.receive_message()
        print(ResponseStatusCode.get_description(code))

        print(value)
        time.sleep(2)

If you want receive RSSI also you must enable it in the configuration

configuration_to_set.TRANSMISSION_MODE.enableRSSI = RssiEnableByte.RSSI_ENABLED

and set the flag to True in the receive_message method

code, value, rssi = lora.receive_message(True)

Result

Success!
pippo

Send dictionary message

Here an example of send data, you can pass a dictionary

lora.send_transparent_dict({'pippo': 'fixed', 'pippo2': 'fixed2'})

lora.send_fixed_dict(0, 0x01, 23, {'pippo': 'fixed', 'pippo2': 'fixed2'})

Here the receiver code

while True:
    if lora.available() > 0:
        code, value = lora.receive_dict()
        print(ResponseStatusCode.get_description(code))
        print(value)
        print(value['pippo'])
        time.sleep(2)

if you want receive RSSI also you must enable it in the configuration

configuration_to_set.TRANSMISSION_MODE.enableRSSI = RssiEnableByte.RSSI_ENABLED

and set the flag to True in the receive_dict method

code, value, rssi = lora.receive_dict(True)

Result

Success!
{'pippo': 'fixed', 'pippo2': 'fixed2'}
fixed

This is a porting of the Arduino library for EBYTE LoRa E22 devices to Micropython

Soon a complete tutorial of the original library on my site www.mischianti.org

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: settings and basic usage
• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: library
• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: configuration
• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: fixed transmission and RSSI
• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: power saving and sending structured data
• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: WOR microcontroller and Arduino shield
• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: WOR microcontroller and WeMos D1 shield
• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: WOR microcontroller and esp32 dev v1 shield

Pinout

E22

Pin No.	Pin item	Pin direction	Pin application
1	M0	Input（weak pull-up）	Work with M1 & decide the four operating modes.Floating is not allowed, can be ground.
2	M1	Input（weak pull-up）	Work with M0 & decide the four operating modes.Floating is not allowed, can be ground.
3	RXD	Input	TTL UART inputs, connects to external (MCU, PC) TXD outputpin. Can be configured as open-drain or pull-up input.
4	TXD	Output	TTL UART outputs, connects to external RXD (MCU, PC) inputpin. Can be configured as open-drain or push-pull output
5	AUX	Output	Per indicare lo stato di funzionamento del modulo e riattivare l’MCU esterno. Durante la procedura di inizializzazione di autocontrollo, il pin emette una bassa tensione. Può essere configurato come uscita open-drain o output push-pull (è consentito non metterlo a terra, ma se hai problemi, ad esempio ti si freeze il dispositivo è preferibile mettere una restistenza di pull-up da 4.7k o meglio collegarlo al dispositivo).
6	VCC		Power supply 2.3V~5.5V DC
7	GND		Ground

As you can see you can set various modes via M0 and M1 pins.

Mode	M1	M0	Explanation
Normal	0	0	UART and wireless channel are open, transparent transmission is on (Supports configuration over air via special command)
WOR Mode	0	1	Can be defined as WOR transmitter and WOR receiver
Configuration mode	1	0	Users can access the register through the serial port to control the working state of the module
Deep sleep mode	1	1	Sleep mode

As you can see there are some pins that can be use in a static way, but If you connect It to the library you gain in performance and you can control all mode via software, but we are going to explain better next.

Fully connected schema

Raspberry Pi

Basic configuration option

ADDH	High address byte of module (the default 00H)	00H-FFH
ADDL	Low address byte of module (the default 00H)	00H-FFH
SPED	Information about data rate parity bit and Air data rate
CHAN	Communication channel（410M + CHAN*1M）, default 17H (433MHz), valid only for 433MHz device chek below to check the correct frequency of your device	00H-1FH
OPTION	Type of transmission, packet size, allow special message
TRANSMISSION_MODE	A lot of parameter that specify the transmission modality

OPTION

Type of transmission, pull-up settings, wake-up time, FEC, Transmission power

SPED detail

UART Parity bit: UART mode can be different between communication parties

4	3	UART parity bit	Constant value
0	0	8N1 (default)	MODE_00_8N1
0	1	8O1	MODE_01_8O1
1	0	8 E1	MODE_10_8E1
1	1	8N1 (equal to 00)	MODE_11_8N1

UART baud rate: UART baud rate can be different between communication parties, The UART baud rate has nothing to do with wireless transmission parameters & won’t affect the wireless transmit / receive features.

7	6	5	TTL UART baud rate（bps）	Constant value
0	0	0	1200	UART_BPS_1200
0	0	1	2400	UART_BPS_2400
0	1	0	4800	UART_BPS_4800
0	1	1	9600 (default)	UART_BPS_9600
1	0	0	19200	UART_BPS_19200
1	0	1	38400	UART_BPS_38400
1	1	0	57600	UART_BPS_57600
1	1	1	115200	UART_BPS_115200

Air data rate: The lower the air data rate, the longer the transmitting distance, better anti- interference performance and longer transmitting time, The air data rate must keep the same for both communication parties.

2	1	0	Air data rate（bps）	Constant value
0	0	0	0.3k	AIR_DATA_RATE_000_03
0	0	1	1.2k	AIR_DATA_RATE_001_12
0	1	0	2.4k (default)	AIR_DATA_RATE_010_24
0	1	1	4.8k	AIR_DATA_RATE_011_48
1	0	0	9.6k	AIR_DATA_RATE_100_96
1	0	1	19.2k	AIR_DATA_RATE_101_192
1	1	0	38.4k	AIR_DATA_RATE_110_384
1	1	1	62.5k	AIR_DATA_RATE_111_625

OPTION detail

####Sub packet setting

This is the max lenght of the packet.

When the data is smaller than the sub packet length, the serial output of the receiving end is an uninterrupted continuous output. When the data is larger than the sub packet length, the receiving end serial port will output the sub packet.

7	6	Packet size	Constant value
0	0	240bytes (default)	SPS_240_00
0	1	128bytes	SPS_128_01
1	0	64bytes	SPS_064_10
1	1	32bytes	SPS_032_11

####RSSI Ambient noise enable

This command can enable/disable the management type of RSSI, It’s important to manage the remote configuration, pay attention isn’t the RSSI parameter in the message.

When enabled, the C0 C1 C2 C3 command can be sent in the transmitting mode or WOR transmitting mode to read the register. Register 0x00: Current ambient noise rssi Register 0X01: rssi when the data was received last time.

5	RSSI Ambient noise enable	Constant value
0	Enable	RSSI_AMBIENT_NOISE_ENABLED
1	Disable (default)	RSSI_AMBIENT_NOISE_DISABLED

TRANSMISSION_MODE Detail

####Enable RSSI

When enabled, the module receives wireless data and it will follow an RSSI strength byte after output via the serial port TXD

####Transmission type

Transmission mode: in fixed transmission mode, the first three bytes of each user’s data frame can be used as high/low address and channel. The module changes its address and channel when transmit. And it will revert to original setting after complete the process.

####Enable repeater function

####Monitor data before transmission

When enabled, wireless data will be monitored before it is transmitted, which can avoid interference to a certain extent, but may cause data delay.

####WOR

WOR transmitter: the module receiving and transmitting functions are turned on, and a wake-up code is added when transmitting data. Receiving is turned on.

WOR receiver: the module is unable to transmit data and works in WOR monitoring mode. The monitoring period is as follows (WOR cycle), which can save a lot of power.

####WOR cycle

If WOR is transmitting: after the WOR receiver receives the wireless data and outputs it through the serial port, it will wait for 1000ms before entering the WOR again. Users can input the serial port data and return it via the wireless during this period. Each serial byte will be refreshed for 1000ms. Users must transmit the first byte within 1000ms.

• Period T = (1 + WOR) * 500ms, maximum 4000ms, minimum 500ms
• The longer the WOR monitoring interval period, the lower the average power consumption, but the greater the data delay
• Both the transmitter and the receiver must be the same (very important).

Send receive message

First we must introduce a simple but usefully method to check if something is in the receiving buffer

int available();

It’s simply return how many bytes you have in the current stream.

Normal transmission mode

Normal/Transparent transmission mode is used to send messages to all device with same address and channel.

LoRa E22 transmitting scenarios, lines are channels

Fixed transmission have more scenarios

LoRa E22 transmitting scenarios, lines are channels

Thanks

Now you have all information to do your work, but I think It’s important to show some realistic examples to undestand better all the possibility.

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: settings and basic usage

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: library

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: configuration

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: fixed transmission and RSSI

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: power saving and sending structured data

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: repeater mode and remote settings

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: WOR microcontroller and Arduino shield

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: WOR microcontroller and WeMos D1 shield

• Ebyte LoRa E22 device for Arduino, esp32 or esp8266: WOR microcontroller and esp32 dev v1 shield