This code is designed to extract data from two sensors, "SparkFun 9DoF Razor IMU M0" board and "SparkFun GPS-RTK-SMA Breakout - ZED-F9P" board, using an Arduino Mega microcontroller. The data is then packed in a custom message format and transmitted via a radio transmitter. The code has multiple boolean flags for each sensor's data stream that are set to true when the start of a message is detected. The data is then read and parsed, and once the end of the message is detected, the boolean flag is set to false. The IMU data is received on Serial1, while the GPS data is received on Serial2. The custom message format is 64 bytes long and includes the sensor data and an encryption key index. The code uses an interval of 400 milliseconds to update the data.
SparkFun 9DoF Razor IMU M0 board (https://www.sparkfun.com/products/16481) SparkFun GPS-RTK-SMA Breakout - ZED-F9P board (https://www.sparkfun.com/products/16481) Radio Transmitter
Arduino IDE
This program uses the following libraries:
string.h ctype.h
Open the Arduino IDE. Connect the hardware. Open the program file. Configure the settings. Upload the code to the microcontroller.
This program does not require any specific settings.
Open the Arduino IDE. Connect the hardware. Open the program file. Configure the settings. Click the "Upload" button in the Arduino IDE to upload the code to the microcontroller.
Connect the radio transmitter to the microcontroller. Turn on the power. The program will begin running automatically. The program will extract data from the IMU and GPS sensors and combine the data into a single message. The program will send the message via the radio transmitter.
This code extracts IMU data from a "SparkFun 9DoF Razor IMU M0" board and GPS data from a "SparkFun GPS-RTK-SMA Breakout - ZED-F9P" board. It then creates its own message and sends it via a radio transmitter.
The code begins by including two standard C libraries: string.h and ctype.h. Then, it initializes some variables and starts the setup process. In the setup, it sets the baud rate for three serial ports, creates a random seed using analogRead(0), and initializes some more variables.
The loop function begins by checking if there is any data available from Serial1 (which should be connected to the GPS). If there is, it reads the data into a character buffer rxstream. The code then checks if the data is part of an IMU message (identified by specific header bytes). If it is, it extracts the necessary data (accelerometer readings and temperature) and sets a flag to indicate that an IMU message has been processed.
Similarly, if the data is part of an Euler message or an EKF-navigation message, the relevant data is extracted, and flags are set. Finally, if the data is part of a GPS RMC message (identified by specific header bytes), the latitude and longitude data are extracted and stored.
When all necessary data has been collected, the code creates its own message by combining the extracted data with some other information (such as a random encryption key index and a pod ID). The message is then sent via a radio transmitter.
msg_c: unsigned int, message counter i: unsigned int, index variable for character buffer rxstream byte_c: byte array, stores the two bytes of msg_c y: char, unused rxstream: char array, buffer to store incoming data msg_tx: char array, stores outgoing message f_euler: boolean, flag indicating that an Euler message has been processed f_nav: boolean, flag indicating that an EKF-navigation message has been processed f_ekf_nav: boolean, flag indicating that an EKF-navigation message has been processed rmc_rd: boolean, flag indicating that a GPS RMC message has been processed f_imu: boolean, flag indicating that an IMU message has been processed indc0-indc9: int, unused tr_angle: unsigned long, unused ac_speed: unsigned long, unused stringGPS: String, stores incoming GPS data rmclat: float, stores latitude extracted from GPS RMC message rmclong: float, stores longitude extracted from GPS RMC message strt_lat: char pointer, unused strt_long: char pointer, unused filedate: unsigned long, unused previousMillis: unsigned long, stores the last time the loop was run interval: long, stores the interval at which to perform the loop (in milliseconds)
The program includes comments to help explain the code. The program was last updated in 2021, and may require updates or modifications to function properly on newer systems.