Serial communication description - makerbase-mks/MKS-SERVO42C GitHub Wiki

Applicable to MKS-SERVO42C-V1.1

Note: Please set the serial port ID first.(default:e0) The default ID for the following chapters is e0.

Read parameter command

command 1 : e0 30 tCHK

read the encoder value (the motor should be calibrated)

Return e0, encoder value(uint16_t), rCHK. The returned value ranges from 0 to FFFF.

Example:

Send e0 30 10

return e0 40 00 20
command 2 : e0 33 tCHK

Read the number of pulses received

Return e0, number pulses(int32_t),rCHK.

Example:

Send e0 33 13

return e0 00 00 01 00 e1 (256 pulses)
command 3 : e0 36 tCHK

read the angle of the motor shaft.

Return e0 , angle(int32_t),rCHK.

The motor rotates one circle, the corresponding angle value range is 0~65535.

Example:

Send e0 36 16

return e0 00 00 40 00 20 (angle 90 °)
command 4: e0 39 tCHK

read the error of the motor shaft angle.

Return e0, error(int16_t), rCHK.

The error is the difference between the angle you want to control minus the real-time angle of the motor, 0-FFFF corresponds to 0~360°, for example, when the angle error is 1°, the return error is 65536/360= 182.444, and so on.

Example:

Send e0 39 19

return e0 00 B7 97 (error 1 °)
command 5: e0 3a tCHK

read the En pins status.

Return e0, status (uint8_t), rCHK.

Status:

01-enable;

02-disable;

00-error

Example:

Send e0 3a 1a

return e0 01 e1 (enable)
command 6: e0 3e tCHK

read the motor shaft status.

Return e0, status (uint8_t), rCHK.

Status:

01-blocked;

02- unblocked;

00-error

Example:

Send e0 3e 1e

return e0 02 e2 (unblocked)

Set system parameter command

Calibrate the encoder （Same as the "Cal" option on screen）

command7 : e0 80 00 tCHK

(The motor must be unloaded.)

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send “e0 80 00 60”

return "e0 01 e1" (succeessful)
Set the motor type （Same as the " MotType " option on screen）

Command8 : e0 81 xx tCHK

xx :

00-0.9° motor;

01-1.8° motor

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 81 01 62" (1.8 degree motor)

return "e0 01 e1" (successful)
Set the work mode （Same as the " CtrMode " option on screen）

Command9 : e0 82 xx tCHK

xx :

00-CR_OPEN;(Open loop mode)

01-CR_vFOC;(Closed loop mode (STP/DIR interface))

02-CR_UART(Closed loop mode (UART interface))

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 82 01 63" (CR_vFOC)

return "e0 01 e1" (successful)
Set the current gear （Same as the " Ma " option on screen）

Command10 : e0 83 xx tCHK

XX:

00-0Ma

01-200Ma

02-400Ma

...

0c-2400Ma

Return e0 and the result (uint8_t) and rCHK.

result:

01- successful;

00- Failure

Example:

Send e0 83 06 69 (1200ma)

return e0 01 e1 (successful)
Set subdivision （Same as the " MStep " option on screen）

Command11 : e0 84 xx tCHK

Set subdivision from 1 to 256, the value will show in the screen of MStep option.

For example:

Send “e0 84 07 6b”，set 7 subdivision

Send “e0 84 4e b2”，set 78 subdivision

Send “e0 84 00 64”，set 256 subdivision

And so on...

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

Example:

Send e0 84 1a 7e (26 subdivision)

return e0 01 e1 (successful)
Set the active of the En pin （Same as the " En " option on screen）

Command12 : e0 85 xx tCHK

xx :

00-active low (L);

01-active high (H);

02-active always (Hold)

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 85 00 65" (active low)

return "e0 01 e1" (successful)
Set the direction of motor rotation（Same as the " Dir " option on screen）

Command13 : e0 86 xx tCHK

xx :

00-CW;

01-CCW

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 86 00 66" (CW)

return "e0 01 e1" (successful)
Set automatic turn off the screen（Same as the " AutoSDD " option on screen）

Command14 : e0 87 xx tCHK

xx :

00-disable;

01-Enable

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 87 00 67" (disable)

return "e0 01 e1" (successful)
Set the stall protection（Same as the " Protect " option on screen）

Command15 : e0 88 xx tCHK

00-Disable

01-Enable

Return e0 and the result (uint8_t) and rCHK.

result:

01- successful;

00- Failure

Example:

Send e0 88 00 68 (Disable)

return e0 01 e1 (successful)
Set the subdivision interpolation function（Same as the " MPlyer " option on screen）

Command16 : e0 89 xx tCHK

xx :

00-disable;

01-Enable

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 89 00 69" (Disable)

return "e0 01 e1" (successful)
Set the baud rate（Same as the " UartBaud " option on screen）

Command17 : e0 8a xx tCHK

xx :

01-9600;

02-19200;

03-25000;

04-38400;

05-57600;

06-115200.

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 8a 04 6e" (38400)

return "e0 01 e1" (successful)
Set the uart address（Same as the " UartAddr " option on screen）

Command18 : e0 8b xx tCHK

xx :

00-e0;

01-e1;

...

09-e9

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 8b 02 6d" (e2)

return "e0 01 e1" (successful)

Set zeroMode parameters command

Set the mode of zeroMode（Same as the " 0_Mode " option on screen）

Command19 : e0 90 xx tCHK

xx :

00-Disable;

01-DirMode;

02-NearMode

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 90 01 71" (DirMode)

return "e0 01 e1" (successful)
Set the zero of zeroMode（Same as the " Set 0 " option on screen）

Command20 : e0 91 xx tCHK

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 91 00 71"

return "e0 01 e1" (successful)

Note: The mode of "0_Mode" needs to be set first.
Set the speed of zeroMode（Same as the " 0_Speed " option on screen）

Command21 : e0 92 xx tCHK

(Range 0~4, the smaller the value, the faster the speed)

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 92 01 72"

return "e0 01 e1" (successful)

Note: The mode of "0_Mode" needs to be set first.
Set the dir of zeroMode（Same as the " 0_Dir " option on screen）

Command22 : e0 93 xx tCHK

xx :

00-CW;

01-CCW

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 93 00 73" (CW)

return "e0 01 e1" (successful)

Note: For NearMode, the setting of 0_Dir should be consistent with the actual running direction of the motor, otherwise it will fail to return to zero.
Return to zero（Same as the " Goto 0 " option on screen）

Command23 : e0 94 00 tCHK

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 94 00 74"

return "e0 01 e1" (successful)

Set PID/ACC/Torque command

Set the position Kp parameter

command24: e0 a1 XX XX tCHK

(Default 0x650).

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 a1 01 20 a2" (Kp = 0x120)

return "e0 01 e1" (successful)
Set the position Ki parameter

command25: e0 a2 XX XX tCHK

(Default 1).

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 a2 00 02 84" (Ki = 0x02)

return "e0 01 e1" (successful)
Set the position Kd parameter

command26: e0 a3 XX XX tCHK

(Default 0x650).

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 a3 02 50 d5" (Kd = 0x250)

return "e0 01 e1" (successful)

Important note: Changing the PID parameters may cause the motor to vibrate, please set the appropriate PID parameters.
Set the acceleration (ACC) parameter

command27: e0 a4 XX XX tCHK

(Default 0x11e).

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 a4 00 80 04" (ACC = 0x80)

return "e0 01 e1" (successful)

Important note: If the ACC parameter is set too large, it may damage the driver board, please set the parameters carefully!
Set the maximum torque (MaxT) parameter

command28: e0 a5 XX XX tCHK

MaxT value range (0 ~ 0x4B0). (Default 0x4B0)

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 a5 02 58 df" (MaxT = 0x258)

return "e0 01 e1" (successful)

Restore default parameter command

command 29: e0 3f tCHK（Same as the " Restore" option on screen）

Return e0 , result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example:

Send "e0 3f 1f"

return "e0 01 e1" (successful)

Note: After restoring the default parameters, you need to power on again and reset the serial port baud rate before serial communication

Serial control command

command 30: e0 f3 xx tCHK

Set the En pin status in CR_UART mode.

status: 01-enable; 00-disable

Return e0, result (uint8_t), rCHK .

result:

01- successful;

00- Failure

Example:

Send e0 f3 01 d4 (enable)

return e0 01 e1 (successful)
command 31: e0 f6 xx tCHK

run the motor forward / reverse in a Constant speed.

Such as:

The XX highest bit indicates direction, and the XX lowest 7 bits indicate 128 speed gears, for example：

The speed(Vrpm) calculation formula is:

Vrpm = (speed × 30000)/(Mstep × 200)(RPM) 1.8°motor

Vrpm = (speed × 30000)/(Mstep × 400)(RPM) 0.9°motor

(Mstep is set by command8 or by the screen menu)

For example:

1.8 degree motor, Mstep = 150, Speed=1

Vrpm = (1 × 30000)/(150 × 200) = 1

Part of the speed is as follows:

Such as:

Send “e0 f6 01 d7”，The motor rotates forward at the speed of 1 gear；

Send “e0 f6 81 57”，The motor reverses at the speed of 1 gear；

Send “e0 f6 5a 30”，The motor rotates forward at the speed of 90 gear；

Send “e0 f6 da b0”，The motor reverses at the speed of 90 gear；

Return e0 ,result (uint8_t),rCHK.

result:

01- successful;

00- Failure

Example:

Send e0 f6 10 e6 (speed of 16 gear)

return e0 01 e1 (successful)
command 32: e0 f7 tCHK

stop the motor.

Return e0 and the result (uint8_t) and rCHK.

result:

01- successful;

00- Failure

Example:

Send e0 f7 d7

return e0 01 e1 (successful)
command 33: e0 ff xx tCHK

Save/Clear the status set in command9.

xx:

c8-save;

ca-clean

Return e0, result (uint8_t), rCHK.

result:

01- successful;

00- Failure

Example: Send e0 ff c8 a7 (save the status)

return e0 01 e1 (successful)

Attention1：The motor can rotates clockwise or counterclockwise at a constant speed when powered on.

Attention2: After the save is successful, the driver board will be disable, and it needs to be re-enabled.

For example:

Step1:

Send e0 f6 10 e6

return e0 01 e1

Step2:

Send e0 ff c8 a7

return e0 01 e1

the motor will always rotates clockwise in speed(16) when power on.
command 34: e0 fd xx xx xx xx xx tCHK

The motor run to an angle in a speed.

The third byte(xx) defines the direction and speed, such as command 9.

The last two bytes(xx xx xx xx ) define the number of pulses.

If(xx xx xx xx = 00 00 0C 80),the motor(1.8 °, subdivision 16) will rotates one circle.

The speed (Vrpm) calculation formula is the same as command10.

Return e0, result (uint8_t), rCHK.

result:

01- successful;

00- Failure

For example: (the motor(1.8 °, subdivision 16))

send “e0 fd 01 00 00 0c 80 6a”, the motor rotates forward 360 °in speed 1.

send “e0 fd 86 00 00 0c 80 ef”, the motor rotates reverses 360 °in speed 6.

Example:

Send e0 fd 32 00 00 0c 80 9b

return e0 01 e1 (successful)