Custom Sensor Interface with v5 Brain

Programming Support
1

@jpearman I’m currently working on interfacing a custom sensor into the brain using vexcode c++. Could you please expand a bit more on the post I linked as to how to setup a generic serial port and receive and integer (or other datatype) input?

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2

What exactly do you need help with? What format is the serial data that you are receiving?

3

so that thread was dealing with Python.

One option is the use the vexlink class in a raw mode, best way is to sub class serial_link to give access to baudrate setting ability, here’s some code to get you started, you can test this as a loopback test using ports 1 and 2.

If all you care about is receiving data from one sensor that just spits it out occasionally, just use a receive link.

example 
/*----------------------------------------------------------------------------*/
/*                                                                            */
/*    Module:       main.cpp                                                  */
/*    Author:       james                                                     */
/*    Created:      11/22/2024, 4:12:19 PM                                    */
/*    Description:  V5 project                                                */
/*                                                                            */
/*----------------------------------------------------------------------------*/
#include "vex.h"

using namespace vex;

// A global instance of vex::brain used for printing to the V5 brain screen
vex::brain       Brain;

// subclass serial_link to allow access to baudrate set function
class sensor_link : public vex::serial_link {
    public:
      // name not used
      // isWired not used, can only be wired if raw link
      sensor_link(int32_t index) : serial_link(index, "name", vex::linkType::raw, true) {
        baud( 115200 );
      }
      virtual ~sensor_link() {
      }
};

// setup ports to send and receive data
sensor_link    tx_link( PORT1 );
sensor_link    rx_link( PORT2 );

int
tx_thread() {
    char *tx_buf = "Hello";

    while(1) {
      tx_link.send(tx_buf, strlen(tx_buf) );

      this_thread::sleep_for(100);
    }

    return 0;
}

int
rx_thread() {
    uint8_t rx_buffer[128];
    
    while(1) {
      if( rx_link.isReceiving() ) {
        int nRead = rx_link.receive( rx_buffer, sizeof(rx_buffer), 50 );

        if( nRead > 0 ) {
          for(int i=0;i<nRead;i++) {
            printf("%02X(%c) ", rx_buffer[i], rx_buffer[i] );
          }
          printf("\n");
        }
      }
      else {
        this_thread::sleep_for(10);
      }
    }

    return 0;
}

int main() {
    thread tx( tx_thread );
    thread rx( rx_thread );

    while(1) {
        
        // Allow other tasks to run
        this_thread::sleep_for(10);
    }
}
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