RS-485 single-wire serial actuator features

          Figure 1.1 Dimensions of the steering gear

1.3 Electrical Connection

1.3.1 Pin Definition

        Figure 1.2 steering gear pin drawing

1. Black -GND ground cable

2, red -VCC power cord

3, white-485 A line

4. Orange-485 B line

1.3.2 Control logic

Electrical Schematic Diagram:

Figure 1.3 Schematic diagram of the steering gear circuit

Serial signal parameter (UART signal parameter) :

Baud rate: 1155200 (default)

Date bit: 8

Stop bit: 1

Patrity: None

Communication mode: Half duplex

1.4 Usage Instructions

The communication mode of this type of steering gear adopts the protocol file of RS485 serial port series intelligent steering gear communication control (serial bus version 5) developed by Desheng Intelligent Technology. RS485 uses balanced transmission and differential reception, with good anti-interference ability, the signal can be transmitted thousands of meters. The receiving and sending of the RS485 share two cables and cannot receive and send at the same time (half-duplex). The controller, as the host, sends read and write instructions to the steering gear, and the steering gear, as the slave, executes the corresponding actions or responses according to the specific situation. Multiple servos are allowed to be mounted on a bus, and each servos on the main line has a unique ID (0~250), the controller can access a specific servos through the servos ID, and can also send data to all servos on the bus through the broadcast ID (254). In addition, the super ID (253) can be used to send query commands to the steering gear on the bus, and the steering gear with different ids will make time-sharing responses.

1.4.1 Cable Connection Procedure

1, the steering gear interface 1 is connected to the blue debugging board A position (according to the circuit diagram to distinguish the pin and positive and negative electrode), if there are more than one steering gear can be connected to other positions A in turn

2. Connect interface 2 to the position of blue debug board B, as shown in Figure a;

3. Adjust the TTL/485 end of the USB-serial port adapter to the 485 end and connect the PC end to the PC end (the debugging board cannot be powered by the computer and the power supply at the same time, pay attention to remove the red power cable of interface 2 beforeconnecting the power supply);

4. After the power port is powered on, open the SSCOM V5.13.1 serial port debugger, as shown in Figure b.

1.4.2 Procedure

1. After the cable connection is complete, open the SSCOM V5.13.1 serial debugger;

2, select the corresponding port of the steering gear in the port number, set the product target baud rate (the default value is 115200), check the HEX display and HEX send functions, click Extend to enter the steering gear command read and write panel;

3, Input the steering gear control instructions in the command sending window (1), copy the input instructions and paste them in the command storage serial port (2), double-click in the window (3) to annotate the instructions and send them; In case of circular transmission, you can set the order of sending instructions in the No. 4 window. After clicking circular transmission, the controller will send instructions in a pre-set order. ⑤ Window No. 5 can control the servo response delay time when a single instruction is sent one by one or several instructions are sent in a loop. After a single instruction is sent or several instructions are sent in a loop, it will be displayed in the ⑥ command display window, where "send" represents the instruction package sent by the controller, and "receive" represents the instruction package answered by the target servo. See Appendix for a detailed list of command functions.

1.4.3 Example Description

This section describes the command format and provides examples to help readers better understand the command and control functions of the steering gear. See the appendix for a detailed list of command functions.

Send frame:

Reply frame:

Frame header: indicates the beginning of the instruction.

ID Number: The sender can use the Super ID(253), Broadcast ID(254), or target gear ID, and the responder returns its own ID.

Data length: The total number of bytes equal to [ID number + instruction function + instruction address + parameter N], that is, =3+N.

Command function: Describes the function types of commands, such as read, write, and firmware update. For details, see Command Function List.

Command address: The address of the command to be read and written. For details, see "Steering Gear Control Command Address List".

Parameter sequence: Send/reply parameters included in the instruction (parameter conversion depending on protocol type).

Checksum= ~((ID +...) + parameter N)&0xFF).

Note 1: The maximum number of bytes in an instruction pack is 256 bytes.

Note 2: The Super ID(253) or target gear ID is required to send the read command, and the broadcast ID(254) has no response.

Example 1 Baud rate read/write instruction _0x10

Instruction send frame: F9 FF 01 03 02 10 E9 instruction function: Read the current baud rate of No. 01 steering gear.

F9 FF: send instruction frame header

01: ID of the steering engine

03: Data length (3+N,N represents parameter sequence, this instruction has no parameter sequence, so N=0)

02: Command function (02 represents the read function in the read and write function)

10: command address (command address 10 stands for reading the current steering gear communication baud rate)

E9: Data check (check bit is calculated by calculator (programmer mode), the specific operations are as follows)

1. Open computer calculator and switch to programmer mode

2, click hexadecimal HEX to add the 01, 03, 02, 10 sequence in the instruction pack to get the result

3. Convert the result according to not and take 2 bits of HEX surface to get the data check bit of the current instruction

Steering gear response frame: F9 F5 01 05 02 10 80 04 63 Command function: The current steering gear communication baud rate is 115200

F9 F5: steering engine response frame header

01: ID of the steering engine

05: Data length (3+N,N represents the parameter sequence, this instruction contains 2 parameter sequences, so N=2)

02: Command function (02 represents the read function in the read and write function)

10: command address (command address 10 represents the current steering gear communication baud rate)

80 04: Parameter sequence (calculated by calculator (programmer mode), specific operations are as follows)

1. Open computer calculator and switch to programmer mode

2. Click hexadecimal HEX to input the current parameter sequence 04 80 (Desun Serial Bus version 5 protocol adopts the small-end mode to send low-byte data first) to convert the decimal DEC to 1152, and the actual communication baud rate is [baud rate value]*100, so the actual communication baud rate of 1152 is 115200.

63: Data check (check bit is calculated by calculator (programmer mode), the specific operation is as follows)

1. Open computer calculator and switch to programmer mode

2, click hexadecimal HEX to add 01, 05, 02, 10, 80, 04 in the instruction pack to get the result

3. Convert the result according to Not and take 2 bits of HEX surface to get the data check bit of the current instruction

Example 2 Servo ID read/write instruction _0x0F

Instruction send frame: F9 FF 01 03 02 0F E9 Instruction function: read the ID number of the current steering gear.

F9 FF: send instruction frame header

01: ID of the steering engine

03: Data length (3+N,N represents parameter sequence, this instruction has no parameter sequence, so N=0)

02: Command function (02 represents the read function in the read and write function)

0F: Command address (command address 0F represents the current steering gear ID number)

E9: Data verification (the verification bit is calculated by the calculator (programmer mode), the specific operation is the same as example 1)

Steering gear response frame: F9 F5 01 04 02 0F 01 E8 Command function: The current steering gear ID number is 01

F9 F5: steering engine response frame header

01: ID of the steering engine

04: Data length (3+N,N represents the parameter sequence, this instruction contains 1 parameter sequence, so N=1)

02: Command function (02 represents the read function in the read and write function)

0F: Command address (command address 0F represents the current steering gear ID number)

01: parameter sequence (calculated by calculator (programmer mode), the specific operation is the same as example 1)

E8: Data check (calculated by calculator (programmer mode), the specific operation is the same as example 1)

Note: Writing the new steering gear ID number can be achieved through the instruction package F9 FF 01 04 03 0F 02 E7. When writing the new ID instruction, if there is a response, the response ID will use the old ID to answer, and then switch to the new ID.

Example 3 Read/write instruction _0x65 for steering gear Angle constant speed control

Instruction send frame: F9 FF 01 07 03 65 46 05 64 00 CC

Command function: No. 01 steering gear rotates from the current position to the 135 degree position (clockwise) at a speed of 100 degrees/second.

F9 FF: send instruction frame header

01: ID of the steering engine

07: Data length (3+N,N represents the parameter sequence, this instruction parameter sequence contains 4 bytes, so N=7)

03: Command function (03 represents the write function in the read and write function)

65: command address (command address 65 represents when the steering gear mode rotation control)

46 05 02 00: parameter sequence (where 46 05 represents target rotation Angle; 64 00 represents the speed of 100 degrees/second (0000 represents the fastest speed), calculated by the calculator (programmer mode), the specific operation is as follows)

1. Open computer calculator and switch to programmer mode

2, click the decimal DEC, the target Angle is 135 degrees, the target speed is 100 degrees/second (Note: deseng 5th edition protocol actual Angle unit is 0.1 degrees, speed unit is degree/second, using the small-end mode, read from right to left), so the actual input Angle value is 1350. The actual input speed value is 100, as shown below.

CC: Data check (in deseng Version 5 protocol, the data check bit can be replaced by CC, or calculated by a calculator (programmer mode), the specific operation is the same as example 1)

1.5 Common Faults

1.5.1 Faults

1.5.2 Frequently Asked Questions

Question 1: The steering gear is fixed on the product, and the positioning deviation is large with the housing?

Answer 1: The steering gear assembly is positioned at the center of the output tooth circle, and the ear holes on both sides are fixed as far as possible.

Question 2: The plastic gear of the steering machine is not impact resistant, easy to skip teeth?

Answer 2: It is necessary to consider the steering gear of the clutch tooth to apply, to avoid the external impact of the product is greater than the blocked torque.

Question 3: The output teeth of the steering gear are damaged by external impact, and the output teeth are not strong enough?

Answer 3: Try to use the steering wheel and product structural parts to support the external impact, to avoid the small output teeth to bear its impact greater than the steering gear torque.

Question4: No communication after the steering gear is connected?

Answer 4: Reinsert the USB serial port and check whether the ID and baud rate of the steering gear are correct.

1.5.3 Precautions

1, please use within the range of working voltage and current, do not overvoltage or overcurrent, so as to avoid burning out or internal damage to the steering gear.

2, please strictly follow the wiring procedure before wiring, so as not to have no function or can not work normally.

3, the use of large torque steering gear must be careful to prevent personal injury caused by misoperation.

4, remember not to add a new steering gear to the bus when the steering gear is working.

5, this product is a high-precision product, do not manually turn the steering wheel or swing arm, so as to avoid internal damage.

6, do not run the steering gear under ultra-high load, try to choose the appropriate running torque.