Control command

The 4 motor interfaces on the module correspond to motors on robot car, as shown below

M1 -> Upper left motor (left front wheel of the car) M2 -> Lower left motor (left rear wheel of the car) M3 -> Upper right motor (right front wheel of the car) M4 -> Lower right motor (right rear wheel of the car)

Serial port configuration

Baud rate 115200, no parity, no hardware flow control, 1 stop bit

1.Configure motor type

0. Motor type selection. If the motor encoder A is connected to the A port of the board, then B is connected to B. You need to select the 310 motor model. Otherwise, you need to select the 520 motor or TT motor.
1. The command can be sent in all uppercase or lowercase letters.
2. If the above command is successful, it will return the message command+OK. If no message is returned, check the serial port connection.
3. x: is the type of motor. The motor types represented by different values are as follows: 1: 520 motor 2: 310 motor 3: TT motor (with encoder) 4: TT motor (without encoder)

Note: If you are using a motor without an encoder, you can select type 4, that is, the command is: $mtype:4# If you are using a motor with an encoder, you can select one of 1, 2, and 3.

2.Configuring motor deadband

1. The command can be sent in all uppercase or all lowercase
2. If the above command is successful, it will return the message of command+OK. If no message is returned, check the serial port connection
3. xxxx: is the value of the dead zone, which needs to be measured. By changing this value, the minimum vibration of the motor can be eliminated
4. The range of the dead zone value (0-3600)

3.Configuring motor phase lines

1. The command can be sent in all uppercase or all lowercase
2. The above command will return command+OK information if it is successful. If no information is returned, check the serial port connection
3. xx: This is the phase of the Hall encoder for one turn. This value needs to be obtained by checking the merchant's motor parameter table
4. For motors with encoders: This value plays a main role in controlling speed. This value needs to be correct
5. Motors without encoders: This value configuration can be ignored

4.Configure motor reduction ratio

1. The command can be sent in all uppercase or all lowercase
2. The above command will return command+OK information if it is successful. If no information is returned, check the serial port connection
3. xx: This is the motor reduction ratio parameter. This value needs to be obtained by checking the merchant's motor parameter table
4. For motors with encoders: This value plays a main role in controlling speed. This value needs to be correct
5. Motors without encoders: This value configuration can be ignored

5.Configure the wheel diameter (Optional)

1. The command can be sent in all uppercase or all lowercase
2. The above command will return command+OK information if it is successful. If no information is returned, check the serial port connection
3. xx: This is the diameter of the wheel. This value can be measured or obtained using the merchant's information
4. For motors with encoders: This value plays a main role in controlling speed. This value needs to be correct in millimeters (mm); if this value is incorrect, it will only affect the speed data inaccurately, and will not affect the encoder data
5. Motors without encoders: This value configuration can be ignored

6.Configure PID parameters for motor control

1. The command can be sent in all uppercase or all lowercase
2. The above command will return command+OK if it is successful. If no information is returned, check the serial port connection
3. x.xx, x.xx, x.xx: These are the parameters for controlling motor p, i, d respectively. Every time the value is changed, the chip will restart and stop the moving motor. This is a normal situation
4. For motors with encoders: the pid parameter is valid, and this value needs to be correct. Generally, there is no need to modify the pid, and the default value can be used
5. Motors without encoders: the pid parameter is invalid, and this value configuration can be ignored

7.Reset all variables to defaults value

1. The command can be sent in all uppercase or all lowercase
2. If the above command is successful, it will return the message command+OK. If no message is returned, check the serial port connection
3. Execute this command and the module will restart once

8.Control speed command

1. The command can be sent in all uppercase or all lowercase letters
2. If the above command is successful, the motor will move, and the serial port will not return anything
3. This command is only valid for encoder type motors.
4. The speed range is (-1000~1000) and it is invalid if it exceeds the range
5. 0,0,0,0: represents M1, M2, M3, M4 on the board screen
6. When the spd command parameter is 0, PID still works. At this time, the hand cannot turn the wheel. To turn the wheel, use the pwm command to set it to 0.

9.Direct control PWM instruction

1. The command can be sent in all uppercase or all lowercase
2. If the above command is successful, the motor will move, and nothing will be returned from the serial port
3. The speed range is (-3600~3600) and it is invalid if it exceeds the range
4. For motor control without encoder, you can control it through this command
5. 0,0,0,0: represents M1,M2,M3,M4 on the board screen

10.Report encoder data (This command is only valid for motors with encoder)

1. The command can be sent in all uppercase or all lowercase
2. $upload:0,0,0#: The first 0 represents: the total encoder data of the wheel rotation The second 0 represents: the real-time encoder data of the wheel rotation (10ms) The third 0 represents: the speed of the wheel
3. The corresponding information can be received at the same time

• The total encoder data of the wheel rotation returns the information: "$MAll:M1,M2,M3,M4#"
• The real-time encoder data of the wheel rotation returns the information: "$MTEP:M1,M2,M3,M4#"
• The speed of the wheel returns the information: "$MSPD:M1,M2,M3,M4#"

11.Query flash variables

1. The command can be sent in all uppercase or all lowercase
2. If the above command is successful, it will return the message command+OK. If no message is returned, check the serial port connection

12.Check battery level

1. The command can be sent in all uppercase or all lowercase
2. If the above command is successful, it will return the information of battery power ($Battery:7.40V#). If no information is returned, please check the serial port connection

IIC protocol control

4-channel motor driver board IIC device address: 0x26