Multiple Range Sensors

[DavidWhelan]

Our FTC team this year were planning on using two range sensors. One on front and one on back. Knowing the I2C address conflict I changed the address of one with the core device discovery and assigned the new I2C address using the method provided with the range sensor class. When I go to read the distance it quires the address 0x28 instead of the address I set it to. Due to this there is an address conflict and I only get distance from the unchanged range sensor,

[AlecHub]

For multiple I2C sensors, you have to use the I2cDevice interface class so that you can specify the I2C address of the sensor. You also have to select I2C Device in configure robot.

package org.firstinspires.ftc.teamcode;

/*
Modern Robotics Range Sensors Example
Created 10/31/2016 by Colton Mehlhoff of Modern Robotics using FTC SDK 2.35
Reuse permitted with credit where credit is due

Configuration:
I2CDevice "range28" (MRI Range Sensor with default I2C address 0x28
I2CDevice "range2a" (MRI Range Sensor with I2C address 0x2a

To change range sensor I2C Addresses, go to http://modernroboticsedu.com/mod/lesson/view.php?id=96
Support is available by emailing support@modernroboticsinc.com.
*/

import com.qualcomm.robotcore.eventloop.opmode.OpMode;
import com.qualcomm.robotcore.eventloop.opmode.TeleOp;
import com.qualcomm.robotcore.hardware.DcMotor;
import com.qualcomm.robotcore.hardware.I2cAddr;
import com.qualcomm.robotcore.hardware.I2cDevice;
import com.qualcomm.robotcore.hardware.I2cDeviceSynch;
import com.qualcomm.robotcore.hardware.I2cDeviceSynchImpl;

@TeleOp(name = "Range Sensors", group = "MRI")
//@Disabled
public class MRI_Range_Sensors extends OpMode {

    byte[] rangeAcache;
    byte[] rangeBcache;

    I2cDevice rangeA;
    I2cDevice rangeB;
    I2cDeviceSynch rangeAreader;
    I2cDeviceSynch rangeBreader;

    @Override
    public void init() {
        telemetry.addData("Status", "Initialized");

        rangeA = hardwareMap.i2cDevice.get("range28");
        rangeB = hardwareMap.i2cDevice.get("range2a");

        rangeAreader = new I2cDeviceSynchImpl(rangeA, I2cAddr.create8bit(0x28), false);
        rangeBreader = new I2cDeviceSynchImpl(rangeB, I2cAddr.create8bit(0x2a), false);

        rangeAreader.engage();
        rangeBreader.engage();
    }

    @Override
    public void loop() {
        rangeAcache = rangeAreader.read(0x04, 2);  //Read 2 bytes starting at 0x04
        rangeBcache = rangeBreader.read(0x04, 2);

        // Ultrasonic value is at index 0. 
        int LUS = rangeAcache[0] & 0xFF;  // & 0xFF creates a value between 0 and 255 instead of -127 to 128
        int RUS = rangeBcache[0] & 0xFF;

        // Optical distance value is at index 1.
        int LODS = rangeAcache[1] & 0xFF;  // & 0xFF creates a value between 0 and 255 instead of -127 to 128
        int RODS = rangeBcache[1] & 0xFF;

        // Display values
        telemetry.addData("1 L US", LUS);
        telemetry.addData("2 L ODS", LODS);
        telemetry.addData("3 R US", RUS);
        telemetry.addData("4 R ODS", RODS);
    }
}

[ansh]

This does not work. The error is that it does not detect the sensors but the sensors are plugged in correctly. What is happening?

[cmacfarl]

Believed to be fixed in https://github.com/ftctechnh/ftc_app/issues/360. Feel free to reopen if not.