(Verified) LoRaUNO development board lora

describe:

This project is based on ATMEGA328P as the main control, and the LoRa module is sx1278

Can realize long-distance data transmission and collection (specifically, the actual measured distance of the LoRa module shall prevail)

Recommended to cooperate with my ESPLoRa project

LORA features : long distance, low power consumption, multi-node, low cost, anti-interference characteristics, and LoRa low rate, small data transmission.

LoRa frequency band: 433/470/868/915MHz frequency band.

Features:

1. The LoRaUNO development board uses the Arduino language for development, so novices can get started quickly. With the addition of 0.96-inch OLED pins, information can be received and sent in real time through the interface. All available pins are lead out, and two sets of 3.3V 5V power supply interfaces can meet the power requirements of most sensors.

2. You can choose the receiving or sending mode through programming definition. There are 255 built-in synchronization channels. Details can be learned through the Arduino_LoRa library.

Design Points:

1. Choose Typec (who doesn’t love the universal C port).

2. Use diodes to prevent reverse connection, ESD5V protection (optional), and self-restoring fuses (optional).

If the fuse is not used, tin the solder joints below! ! !

3. Use CH340N to reduce the size.

4. The indicator lights are: Power TX D7 can choose different lamp bead colors to indicate status.

5. Two voltage regulator chips AMS1117-5.0 and AMS1117-3.3 are used to power ATMEGA328P and LoRa respectively to increase the overall circuit stability.

The AMS1117-5.0 voltage drop is a bit large. The actual measurement does not affect the use.

6. I chose the patch method for the ATMEGA328P crystal oscillator. In order to save space, I can change it to a direct plug-in type if necessary.

7. This time, the SMA antenna is used in the package, which can be easily disassembled to enhance the signal quality.

Precautions:

1. The pins used by LoRa are not recommended to be used again.

2. Two sets of 3.3V 5V power supply interfaces can supply power to most sensors.

3. If you have a brand new ATMEG328p, there is no bootloader (BootLoader) in it, and the module does not lead to ICSP in order to save volume. You can burn the BootLoader through the LoRa pins D11, D12, and D13 before soldering the LoRa module .

4. The pin order of the OLED display is different. Mine is that the first pin is GND.

5. The LoRa antenna must be welded, otherwise the module will be easily damaged.

6. The capacitor of the antenna does not need to be soldered. In order to improve the signal quality, 100nF can be soldered.