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This is a porting of the Arduino library for EBYTE LoRa E32 devices to RaspberryPi

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A complete tutorial on my site www.mischianti.org

1. LoRa E32 device for Arduino, esp32 or esp8266: settings and basic usage
2. LoRa E32 device for Arduino, esp32 or esp8266: library
3. LoRa E32 device for Arduino, esp32 or esp8266: configuration
4. LoRa E32 device for Arduino, esp32 or esp8266: fixed transmission
5. LoRa E32 device for Arduino, esp32 or esp8266: power saving and sending structured data
6. LoRa E32 device for Arduino, esp32 or esp8266: WOR (wake on radio) the microcontroller and Arduino shield
7. LoRa E32 device for Arduino, esp32 or esp8266: WOR (wake on radio) microcontroller and new WeMos D1 mini shield

Changelog

• 2023-12-27 0.0.3 Fix json requirements
• 2023-05-02 0.0.2 Fix 900MHz devices frequency
• 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-e32-rpi

Initialization

from lora_e32 import LoRaE32
import serial

loraSerial = serial.Serial('/dev/serial0') #, baudrate=9600, parity=serial.PARITY_NONE, stopbits=serial.STOPBITS_ONE, bytesize=serial.EIGHTBITS)
lora = LoRaE32('433T20D', loraSerial, aux_pin=18, m0_pin=23, m1_pin=24)

Start the module transmission

code = lora.begin()
print(ResponseStatusCode.get_description(code))

Get Configuration

from lora_e32 import LoRaE32, print_configuration, Configuration
from lora_e32_operation_constant import ResponseStatusCode

code, configuration = lora.get_configuration()

print(ResponseStatusCode.get_description(code))
print_configuration(configuration)

The result

----------------------------------------
HEAD : 0b11000000 192

AddH : 0
AddL : 2
Chan : 23  ->  433

SpeedParityBit    : 0b0  ->  8N1 (Default)
SpeedUARTDatte : 0b11  ->  9600bps (default)
SpeedAirDataRate  : 0b10  ->  2.4kbps (default)
OptionTrans       : 0b1  ->  Fixed transmission (first three bytes can be used a
s high/low address and channel)
OptionPullup      : 0b1  ->  TXD, RXD, AUX are push-pulls/pull-ups (default)    
OptionWakeup      : 0b0  ->  250ms (default)
OptionFEC         : 0b1  ->  Turn on Forward Error Correction Switch (Default)
OptionPower       : 0b0  ->  20dBm (Default)
----------------------------------------

Set Configuration

configuration_to_set = Configuration('433T20D')
configuration_to_set.ADDL = 0x02
configuration_to_set.OPTION.fixedTransmission = FixedTransmission.FIXED_TRANSMISSION

code, confSetted = lora.set_configuration(configuration_to_set)

The configuration object has a lot of parameters.

class Configuration:
class Speed:
    def __init__(self, model):
        self.model = model

        self.airDataRate = AirDataRate.AIR_DATA_RATE_010_24
        self.uartBaudRate = UARTBaudRate.BPS_9600
        self.uartParity = UARTParity.MODE_00_8N1

class Option:
    def __init__(self, model):
        self.model = model

        self.transmissionPower = TransmissionPower(self.model).get_transmission_power().get_default_value()
        self.fec = ForwardErrorCorrectionSwitch.FEC_1_ON
        self.wirelessWakeupTime = WirelessWakeUpTime.WAKE_UP_250
        self.ioDriveMode = IODriveMode.PUSH_PULLS_PULL_UPS
        self.fixedTransmission = FixedTransmission.TRANSPARENT_TRANSMISSION

class Configuration:
    def __init__(self, model):
        self.HEAD = 0
        self.ADDH = 0
        self.ADDL = 0
        self.SPED = Speed(model)
        self.CHAN = 23
        self.OPTION = Option(model)

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)

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)

Result

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

Wiring

Raspberry Pi

LoRa E32 (EBYTE LoRa SX1278/SX1276) series Library for Arduino, esp8266 and esp32-

I create a library to manage EBYTE E32 series of LoRa device, very powerfull, simple and cheap device.

LoRa E32-TTL-100

You can find here AliExpress (3Km device) AliExpress (8Km device)

They can work over a distance of 3000m to 8000m, and they have a lot of features and parameter.

So i create this library to simplify the usage.

Please refer to my article to get updated Schema

Library

You can find my library here.

To download.

Click the DOWNLOADS button in the top right corner, rename the uncompressed folder LoRa_E32.

Check that the LoRa_E32 folder contains LoRa_E32.cpp and LoRa_E32.h.

Place the LoRa_E32 library folder your /libraries/ folder.

You may need to create the libraries subfolder if its your first library.

Restart the IDE.

Pinout

E32 TTL 100

You can buy here AliExpress

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

As I already say It’s not important to connect all pin to the output of microcontroller, you can put M0 and M1 pins to HIGH or LOW to get desidered configuration, and if you don’t connect AUX the library set a reasonable delay to be sure that the operation is complete.

AUX pin

When transmitting data can be used to wake up external MCU and return HIGH on data transfer finish.

LoRa E32 AUX Pin on transmission

When receiving AUX going LOW and return HIGH when buffer is empty.

LoRa e32 AUX pin on reception

It’s also used for self checking to restore normal operation (on power-on and sleep/program mode).

LoRa e32 AUX pin on self-check

esp8266 connection schema is more simple because It work at the same voltage of logical communications (3.3v).

LoRa E32 TTL 100 Wemos D1 fully connected

It’s important to add pull-up resistor (4,7Kohm) to get good stability.

Arduino working voltage is 5v, so we need to add a voltage divider on RX pin M0 and M1 of LoRa module to prevent damage, you can get more information here Voltage divider: calculator and application.

You can use a 2Kohm resistor to GND and 1Kohm from signal than put together on RX.

LoRa E32 TTL 100 Arduino fully connected

Basic configuration option

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

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.

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.

OPTION detail

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.

IO drive mode: this bit is used to the module internal pull- up resistor. It also increases the level’s adaptability in case of open drain. But in some cases, it may need external pull-up
resistor.

Wireless wake-up time: the transmit & receive module work in mode 0, whose delay time is invalid & can be arbitrary value, The transmitter works in mode 1 can transmit the preamble code of the corresponding time continuously, when the receiver works in mode 2, the time means the monitor interval time (wireless wake-up). Only the data from transmitter that works in mode 1 can be
received.

FEC: after turn off FEC, the actual data transmission rate increases while anti- interference ability decreases. Also the transmission distance is relatively short, both communication parties must keep on the same pages about turn-on or turn-off FEC.

Transmission power

You can change this set of constant by apply a define like so:

Applicable for E32-TTL-100, E32-TTL-100S1, E32-T100S2.
The external power must make sure the ability of current output more than 250mA and ensure the power supply ripple within 100mV.
Low power transmission is not recommended due to its low power supply
efficiency.

Applicable for E32-TTL-500。
The external power must make sure the ability of current output more than 700mA and ensure the power supply ripple within 100mV.
Low power transmission is not recommended due to its low power supply efficiency.

Applicable for E32-TTL-1W, E32 (433T30S), E32 (868T30S), E32 (915T30S)
The external power must make sure the ability of current output more than 1A and ensure the power supply ripple within 100mV.
Low power transmission is not recommended due to its low power supply
efficiency.

You can configure Channel frequency olso with this define:

Normal transmission mode

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

LoRa E32 transmitting scenarios, lines are channels

Fixed mode instead of normal mode

At same manner I create a set of method to use with fixed transmission

Fixed transmission

You need to change only the sending method, because the destination device don’t receive the preamble with Address and Channel.

Fixed transmission have more scenarios

Thanks