How to control 2 AX12W independently with OpenCR 1.0

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You are confusing me now. You are using Arduino IDE with OpenCR and I am assuming that you have installed the OpenCR board via the Board Manager - so why would you need to use the Arduino UNO + Shield? Also have you installed the Dynamixel2Arduino library? If you have done these 2 tasks, there should be a bunch of example sketches showing how to control the DXLs from OpenCR directly.

image

Below is a complete Arduino sketch testing some XL-430 with OpenCR-1 and the Dynamixel2Arduino library:

#include <Dynamixel2Arduino.h>

#define DXL_SERIAL   Serial3  // for OpenCR
#define DEBUG_SERIAL Serial
const int DXL_DIR_PIN = 84; // OpenCR Board's DIR PIN.
const uint8_t DXL_ID = 1;
const float DXL_PROTOCOL_VERSION = 2.0;  // 1.0 for AX-12

Dynamixel2Arduino dxl(DXL_SERIAL, DXL_DIR_PIN);

//This namespace is required to use Control table item names
using namespace ControlTableItem;

void setup() {
  // put your setup code here, to run once:
  
  // Use UART port of DYNAMIXEL Shield to debug.
  DEBUG_SERIAL.begin(115200);
  while(!DEBUG_SERIAL);
  
  // Set Port baudrate to 1000000 bps. This has to match with DYNAMIXEL baudrate.
  dxl.begin(1000000);
  // Set Port Protocol Version. This has to match with DYNAMIXEL protocol version.
  dxl.setPortProtocolVersion(DXL_PROTOCOL_VERSION);
  // Get DYNAMIXEL information
  dxl.ping(DXL_ID);

  // Turn off torque when configuring items in EEPROM area
  dxl.torqueOff(DXL_ID);
  dxl.setOperatingMode(DXL_ID, OP_VELOCITY);
  dxl.torqueOn(DXL_ID);
}

void loop() {
  // Set Goal Velocity using RAW unit
  dxl.setGoalVelocity(DXL_ID, 200);
  delay(1000);
  // Print present velocity
  DEBUG_SERIAL.print("Present Velocity(raw) : ");
  DEBUG_SERIAL.println(dxl.getPresentVelocity(DXL_ID));
  delay(1000);

  // Set Goal Velocity using RPM
  dxl.setGoalVelocity(DXL_ID, 25.8, UNIT_RPM);
  delay(1000);
  DEBUG_SERIAL.print("Present Velocity(rpm) : ");
  DEBUG_SERIAL.println(dxl.getPresentVelocity(DXL_ID, UNIT_RPM));
  delay(1000);

  // Set Goal Velocity using percentage (-100.0 [%] ~ 100.0 [%])
  dxl.setGoalVelocity(DXL_ID, -10.2, UNIT_PERCENT);
  delay(1000);
  DEBUG_SERIAL.print("Present Velocity(ratio) : ");
  DEBUG_SERIAL.println(dxl.getPresentVelocity(DXL_ID, UNIT_PERCENT));
  delay(1000);
}

To make it work with AX-12s, all you have to do is to change DXL_PROTOCOL_VERSION = 1.0

OpenCR_Velocity_Mode

Below is a picture of my physical setup:

IMG_026488

And a video clip of a SyncWriteRead sketch (using 2XL430):