3DR Radio Telemetry 915 MHz Documentation

Frequency Band

915 MHz

Transmission Power

Up to 1 W

Sensitivity

-115 dBm

Data Transmission Rate

Up to 250 kbps

Range

Up to 40 km (25 miles)

Latency

<20 ms

Operating Temperature

-20C to 60C

Weight

Airborne Radio - 14 grams, Ground Radio - 50 grams

Dimensions

Airborne Radio - 30 x 20 x 10 mm, Ground Radio - 60 x 40 x 20 mm

Conclusion

The 3DR Radio Telemetry 915 MHz is a reliable and high-performance radio telemetry system designed for demanding drone and UAV applications. Its long-range capability, high-speed data transmission, and low latency make it an ideal choice for applications requiring real-time communication and control.

Pin Configuration

3DR Radio Telemetry 915 MHz Pinout Guide
The 3DR Radio Telemetry 915 MHz is a popular IoT component used for wireless communication in unmanned aerial vehicles (UAVs) and other robotics applications. This documentation provides a comprehensive guide to the pinout and connection structure of the 3DR Radio Telemetry 915 MHz module.
Pinout Description:
The 3DR Radio Telemetry 915 MHz module has a total of 12 pins, divided into two rows of 6 pins each. The pins are labeled as follows:
Row 1:
1. VCC (Pin 1): Power supply pin, typically connected to a 5V power source.
Connection: Connect to a 5V power supply or a voltage regulator output.
2. GND (Pin 2): Ground pin, connected to the system's ground plane.
Connection: Connect to the system's ground plane or a common ground point.
3. UART_TX (Pin 3): Transmit pin for serial communication (UART protocol).
Connection: Connect to the receive (RX) pin of a UART-enabled microcontroller or device.
4. UART_RX (Pin 4): Receive pin for serial communication (UART protocol).
Connection: Connect to the transmit (TX) pin of a UART-enabled microcontroller or device.
5. RSSI (Pin 5): Received Signal Strength Indicator pin, providing a voltage output proportional to the received signal strength.
Connection: Connect to an ADC (Analog-to-Digital Converter) input on a microcontroller or a voltage monitoring circuit.
6. GPIO1 (Pin 6): General-purpose input/output pin, can be used for various purposes such as button interfaces or LED indicators.
Connection: Connect to a microcontroller's GPIO pin or a custom circuitry.
Row 2:
1. GPIO2 (Pin 7): General-purpose input/output pin, can be used for various purposes such as button interfaces or LED indicators.
Connection: Connect to a microcontroller's GPIO pin or a custom circuitry.
2. GPIO3 (Pin 8): General-purpose input/output pin, can be used for various purposes such as button interfaces or LED indicators.
Connection: Connect to a microcontroller's GPIO pin or a custom circuitry.
3. SPI_CLK (Pin 9): Clock pin for Serial Peripheral Interface (SPI) communication.
Connection: Connect to the SPI clock pin on a microcontroller or a compatible SPI device.
4. SPI_MOSI (Pin 10): Master Out Slave In pin for SPI communication.
Connection: Connect to the MOSI pin on a microcontroller or a compatible SPI device.
5. SPI_MISO (Pin 11): Master In Slave Out pin for SPI communication.
Connection: Connect to the MISO pin on a microcontroller or a compatible SPI device.
6. ANT (Pin 12): Antenna connection pin, used for connecting the radio telemetry module to an external antenna.
Connection: Connect to a 915 MHz antenna or a compatible RF connector.
Connection Structure:
To connect the 3DR Radio Telemetry 915 MHz module to a microcontroller or a compatible device, follow these steps:
1. Power the module by connecting the VCC pin to a 5V power supply and the GND pin to the system's ground plane.
2. Connect the UART_TX pin to the RX pin on the microcontroller and the UART_RX pin to the TX pin on the microcontroller.
3. Connect the RSSI pin to an ADC input on the microcontroller or a voltage monitoring circuit.
4. Use the GPIO pins (GPIO1, GPIO2, and GPIO3) for custom interfaces or connections as needed.
5. For SPI communication, connect the SPI_CLK pin to the SPI clock pin on the microcontroller, the SPI_MOSI pin to the MOSI pin, and the SPI_MISO pin to the MISO pin.
6. Connect the ANT pin to a compatible 915 MHz antenna or RF connector.
Important Notes:
Ensure proper power supply and voltage regulation to the module to avoid damage.
Use suitable antennas or RF connectors to maintain optimal radio frequency performance.
Consult the datasheet and technical documentation for specific configuration and usage guidelines.
By following this pinout guide and connection structure, you can successfully integrate the 3DR Radio Telemetry 915 MHz module into your IoT project or application.

Code Examples

3DR Radio Telemetry 915 MHz Documentation

Overview

The 3DR Radio Telemetry 915 MHz is a wireless communication module designed for IoT applications, specifically for drone and robotics systems. It operates on the 915 MHz frequency band, providing a reliable and efficient data transmission solution.

Technical Specifications

Frequency: 915 MHz
 Data Rate: Up to 250 kbps
 Range: Up to 1 km (depending on environment and antenna configuration)
 Power Consumption: 100 mA (transmit), 20 mA (receive)
 Interface: UART (Serial)

Code Examples

### Example 1: Basic Telemetry Transmission using Arduino

In this example, we'll demonstrate how to use the 3DR Radio Telemetry module to transmit telemetry data from an Arduino board to a remote receiver.

Sender Code (Arduino)
```c++
#include <SoftwareSerial.h>

#define TELEM_BAUD 57600
#define RADIO_PIN_TX 2
#define RADIO_PIN_RX 3

SoftwareSerial radio(RADIO_PIN_TX, RADIO_PIN_RX);

void setup() {
  radio.begin(TELEM_BAUD);
  Serial.println("Telemetry transmitter started");
}

void loop() {
  // Sample telemetry data (e.g., sensor readings)
  int sensor1 = analogRead(A0);
  int sensor2 = analogRead(A1);

// Create a telemetry packet
  char telemetryPacket[20];
  sprintf(telemetryPacket, "Sensor1: %d, Sensor2: %d", sensor1, sensor2);

// Transmit the telemetry packet
  radio.println(telemetryPacket);
  delay(100);
}
```
Receiver Code (Python)
```python
import serial

# Open the serial port connected to the receiver
ser = serial.Serial('/dev/ttyUSB0', 57600, timeout=1)

while True:
    # Read incoming telemetry data
    telemetry_data = ser.readline()
    if telemetry_data:
        print(telemetry_data.decode().strip())
```
### Example 2: Integrating with PX4 Autopilot System

In this example, we'll demonstrate how to integrate the 3DR Radio Telemetry module with the PX4 Autopilot System, a popular open-source autopilot software.

px4-sitl Configuration
```bash
# Configure the telemetry radio
TELEM_RADIO_TYPE=3DR
TELEM_RADIO_BAUD=57600
TELEM_RADIO_DEVICE=/dev/ttyUSB0
```
PX4 Code (C++)
```c++
#include <px4_platform_common/defines.h>
#include <px4_time.h>
#include <uORB/topics/vehicle_attitude.h>

// Initialize the telemetry radio
telemetry_radio_init();

while (!_px4_shutdown_requested) {
    // Get the vehicle attitude data
    vehicle_attitude_s att;
    orb_copy(ORB_ID(vehicle_attitude), &_vehicle_attitude_pub, &att);

// Create a telemetry packet
    char telemetry_packet[20];
    sprintf(telemetry_packet, "Roll: %f, Pitch: %f, Yaw: %f", att.roll, att.pitch, att.yaw);

// Transmit the telemetry packet
    telemetry_radio_send(telemetry_packet, strlen(telemetry_packet));
    usleep(100000);
}
```
These examples demonstrate the basic usage of the 3DR Radio Telemetry 915 MHz module in IoT applications. The module can be used in various contexts, including drone systems, robotics, and IoT sensor networks.