RYLR998 UART Interface 868/915 MHz Lora Module with Antenna FCC CE NCC Certification

Very easy to use over UART and AT commands. Seems to have a powerful radio with effective antenna. I've purchased a handful of these already.

The media could not be loaded. So I had ChatGPT craft python code that did random byte send and pushed the RYLR998 to the breaking point. I had the code send random length characters with payloads up to 32 Bytes with no delay and then had Python graph the throughput. The data stream capped out at about 3,500 Bps before the frame buffer became overloaded. Overall I am impressed with the ease of use, the fact it uses simple easily understood AT commands, the simple wiring to a USB TTL interface, and general performance when I hammer it with garbage to send.

Connecting a **REYAX RYLR998 UART Interface 868/915 MHz LoRa Module** to a **Flipper Zero** is a fun project that can extend the Flipper’s capabilities with long-range wireless communication. The RYLR998 uses a UART interface, and the Flipper Zero has GPIO pins that can be configured for UART communication. Below is a step-by-step guide to help you connect and use these devices together.### What You’ll Need1. **REYAX RYLR998 LoRa Module** (with its built-in antenna).2. **Flipper Zero**.3. **Jumper wires** (female-to-male or male-to-male, depending on your setup).4. **Optional**: A USB-to-UART adapter (e.g., FTDI or CP2102) for initial testing or configuration of the RYLR998.5. **Basic Tools**: A computer with a terminal program (e.g., PuTTY, Tera Term, or the Flipper Zero’s qFlipper app) for testing.### Step 1: Understand the Hardware- **RYLR998 Pinout**: The RYLR998 is a compact LoRa transceiver with a UART interface. Its key pins are:- **VDD**: Power supply (2.0V to 3.6V; 3.3V is typical).- **GND**: Ground.- **TXD**: UART transmit (data out from RYLR998).- **RXD**: UART receive (data in to RYLR998).- **NRST**: Reset pin (optional, can be left unconnected for basic use).- **Flipper Zero GPIO**: The Flipper Zero has a 1.8V/3.3V-compatible GPIO header. You’ll use two pins as UART TX and RX, plus power pins (3.3V and GND). Check the Flipper Zero pinout (available in its documentation) to pick suitable pins—commonly, GPIO 13 (TX) and 14 (RX) are used for UART.### Step 2: Wiring the ConnectionSince the Flipper Zero operates at 3.3V logic and the RYLR998 is compatible with 3.3V, you can connect them directly:1. **Power**:- Connect **VDD** on the RYLR998 to the **3.3V pin** on the Flipper Zero.- Connect **GND** on the RYLR998 to a **GND pin** on the Flipper Zero.2. **UART**:- Connect **TXD** (RYLR998) to **RX (GPIO 14)** on the Flipper Zero.- Connect **RXD** (RYLR998) to **TX (GPIO 13)** on the Flipper Zero.3. **Reset (Optional)**:- Leave **NRST** floating or connect it to a GPIO pin if you want to control reset programmatically (e.g., GPIO 15).Double-check your connections to avoid shorts or incorrect wiring.### Step 3: Configure the RYLR998The RYLR998 uses AT commands over UART to configure settings like frequency, address, and network ID. Out of the box, it might not be set up to communicate immediately, so you may need to configure it first:- **Initial Test (Optional)**: Use a USB-to-UART adapter to connect the RYLR998 to your computer (TXD to RX, RXD to TX, 3.3V, GND). Open a terminal (baud rate: 115200, 8N1) and test with `AT` (should reply `+OK`).- **Key Commands**:- `AT+ADDRESS=1`: Set a unique address (e.g., 1).- `AT+NETWORKID=5`: Set a network ID (e.g., 5).- `AT+BAND=915000000`: Set frequency (e.g., 915 MHz for the US; use 868 MHz if in Europe).- `AT+PARAMETER=10,7,1,7`: Set spreading factor, bandwidth, coding rate, and preamble (adjust as needed).- Once configured, disconnect it from the computer and wire it to the Flipper Zero.### Step 4: Set Up the Flipper ZeroThe Flipper Zero doesn’t have a built-in LoRa app (as of February 26, 2025), but you can use its GPIO UART functionality via custom firmware or scripts:1. **Install Custom Firmware (Optional)**: Check the Flipper Zero community (e.g., GitHub or the Flipper Zero Discord) for firmware with UART or LoRa support. The “RogueMaster” or “Unleashed” firmware might have relevant plugins.2. **Use the UART Bridge**: The stock firmware includes a UART Bridge app (under GPIO settings). Set it to 115200 baud, and you can send AT commands directly from the Flipper’s screen.3. **Scripting**: Write a simple script using the Flipper’s Sub-GHz or GPIO tools to send/receive data via UART. For example:- Send: `AT+SEND=1,5,Hello` (sends “Hello” to address 1, 5 bytes).- Receive: Watch for `+RCV=<address>,<length>,<data>` responses.### Step 5: Test the Connection- Power on the Flipper Zero and the RYLR998.- Use the UART Bridge or a custom script to send an AT command (e.g., `AT+ADDRESS?` to check the address).- If you have a second RYLR998 (connected to another device), send a message like `AT+SEND=1,5,Test` and verify reception.### Notes and Tips- **Power**: The Flipper Zero’s 3.3V pin should supply enough current for the RYLR998 (~20mA RX, ~120mA TX), but monitor battery drain during testing.- **Range**: With its built-in antenna, the RYLR998 can achieve several kilometers in open areas, though walls and interference will reduce this.- **Safety**: Ensure your frequency (868 or 915 MHz) complies with local regulations (e.g., FCC in the US, CE in Europe).- **Firmware Limits**: If the stock Flipper firmware lacks robust UART support for your needs, explore community-developed options or write a custom app using the Flipper Zero SDK.### Troubleshooting- No response? Check wiring, baud rate (115200), and power.- Garbled data? Ensure the Flipper’s UART pins match your configuration.- Range issues? Test with another RYLR998 to confirm both modules work.With this setup, your Flipper Zero can send and receive LoRa messages via the RYLR998, opening up possibilities for long-range hacking, IoT experiments, or just messing around. Have fun!

Amazing little units that are super easy to use. Love it!

[Edit 2024-05-13]Regarding stability: I wrote some C code, replacing the micropython, and found that the key to getting reliability is not to simply DELAY, but to always check for +OK or +ERR after each time sending data to the LoRa module, including when setting up configuration. The code works fine without a single sleep,, and spends most of its time waiting for serial input from the module. I am not counting +RCV as confirmation for the previous request sent over serial to the module.[Edit 2024-05-09]Did some distance testing, had an echo-server on second floor at home, and another with me, which lit a led while getting echoes in return, and turning it off if no data received. There are a bit of both low and high buildings here, and I am impressed with the range. Did not see signal strength, only success or failure, through the led, but got clear signals at least 3-400 meters away, through some threes, and even behind small bumps in the landscape. I had been worried that having only one inside the house would greatly limit range, if not in line with a window, but that didn't seem to matter. Incredible little radios!![Original review]I started out using an FTDI chip from my Linux PC, but got +ERR=1 on every keypress. It seems the terminal emulators I tried sent each keypress, instead of buffering up a line, and send it followed by \r\n which the LoRa chip expects.So I hooked up two Raspberry Pi Pico to control the LoRa modules, and in front of that, two Raspberry Pi, flashing them with micropython and developing with thonny.Getting the first message across was easy, but it felt unreliable. After some testing I figured out that after each command is sent to the LoRa module, it is best to delay a couple of seconds before the next, as well as reading any serial input as well before the next command.I tried connecting from basement to two floors up, and it works great, at -50 signal strength.I am very satisfied with the result so far, and look forward to do outdoor testing.

This device works excellent and the range is very good.Best I have tested so far and easy to setup and code.I was able to send some Arduino Json payloads.

I tried both the REYAX RYLR896 and the RYLR998 because I wanted the ability to set the address, network ID, etc. These REYAX modules will frustrate you. I dealt with weird inconsistent issues. Maybe try them with the Arduino mini? I am using the Arduino and the Nano which required a voltage divider. I watched lots of YouTube videos and read many online posts that provided examples. I would get them to work and then they would fail. I'm going back to Maduino from Makerfabs Product Code: OAC915MLR for LoRa connectivity. Good luck if you decide to try these.

Good