SEW EURODRIVE MOVIDYN communication interface

The main station sends ENQUIRY frames:

Frame identifier: B5 (85 hex)

Address: 0C (12)

Index: 00 03 (radiator temperature)

Checksum: B5+0C+00+03=C4

Full frame: B5 0C 00 03 C4

Reply to DATA frame from the station (assuming a temperature of 25.5 ° C, with values represented as 00 00 25 50):

Frame identifier: C8

Index: 00 03

Value: 00 00 25 50

Checksum: C8+00+03+00+00+25+50=0140 → 40

Full frame: C8 00 03 00 00 25 50 40

3.2 Write the first acceleration ramp time (CW) as 3.7 seconds

The index of parameter "Slope 1 to CW" is 001F (31), and the value of 3.7 seconds is represented as 00000 370.

The main station sends a SELECT frame:

Identifier: A9

Address: 0C

Index: 00 1F

Value: 00 00 03 70

Checksum: A9+0C+00+1F+00+00+03+70=0147 → 47

Full frame: A9 0C 00 1F 00 00 03 70 47

Reply ACK from the slave station: D2 D2

3.3 Writing IPOS Variables (IPOS Options Only)

Taking the example of writing variable 5 with a value of 123000 (1E078 hex) to address 1. Two steps are required: first select the variable pointer, and then write the data value.

Step 1: Write variable number 5 to index 715 (data pointer)

Index 715=02CB hex

SELECT frame: A9 01 02 CB 00 00 05 00, checksum 7C

Reply ACK from the station

Step 2: Write the value 1E078 to index 1011 (data value) using a LONG_SELECT frame (8-byte value)

Index 1011=03F3 hex

Value: 00 00 00 01 0E 00 07 08 (small end? The original text is 00 00 00 01 0E 00 07 08, which actually represents 1E078

Frame: AD 01 03 F3 00 00 01 0E 00 07 08, checksum is 00+00+00+01+0E+00+07+08=C2 (low byte)

Reply ACK from the station

3.4 Reading IPOS Variables

Similar steps: First, write the variable number to index 715, then send ENQUIRY to index 1011, and the slave station replies with a LONG-DATA frame.

API/APA positioning module specific protocol

The API/APA option card uses ASCII protocol, and user data is readable ASCII commands. Its message header is related to MOVIDYN ®  The protocol is different, and the frame identifier is fixed as BB hex.

4.1 Frame header structure

Byte Content Description

0-frame identifier (BB) distinguishes API/APA

Unit 1 address 0~59

2-Status Byte (SB) Bit Mapping Control

3 Data Length (NL) User data bytes+checksum

4... n-1 User Data ASCII Command

Checksum (CS) SB+NL+sum of user data (+address optional)

Status byte bit definition:

Bit 0:0=ENQUIRY, 1=SELECT

Bit 3: Is ACK/NACK acknowledgement required (valid only for SELECT frames)

Bit 4: Should the axis address be included in the checksum calculation

Bit 5: Should the checksum range be shortened (0-7F)

4.2 API/APA Frame Types

ENQUIRY frame: Request data. For example, the command% RD H00 reads the variable H00.

SELECT frame: Write data. For example, command% H00:10; Set the variable H00 to 10.

DATA frame: In response to ENQUIRY, return the requested data (ASCII string).

ACK frame: Confirm successful SELECT, data value is 06 hex.

NACK frame: Report an error with a data value of 15 hex and attach error information (error number, program number, line number, etc.).

4.3 Application Example: Requesting API/APA Status

Send command? The status string can be obtained, and the return format includes:

G... actual location

H... Target location

O... hysteresis error

I... Locate processor status (hexadecimal)

K... Digital input status

L... digital output status

M... current active program number

N... current line number

P... Hardware limit switch status

Example: Requesting only the actual location:? G， Return a string similar to G1234.

If an error occurs, an error sequence starting with Z will be inserted in the response, including the error identifier, error number, error type, program number, line number, etc.

Technical parameters and connections of RS-232 and RS-485 interfaces

5.1 RS-232 interface

Standard: DIN 66020 (V.24)

Baud rate: 9600 baud

Data format: 1 start bit, 8 data bits, 1 stop bit, no parity check

Working mode: asynchronous, half duplex

Maximum cable length: 5 meters (recommended)

Connector: 9-pin Sub-D, only using pins 2 (TXD), 3 (RXD), 4 (DTR), 5 (GND)

The PC is connected to X01 of MPB through a standard serial cable or to MPR/MKS through USS11. The DTR signal is used to control RS-485 direction switching.

5.2 RS-485 interface

Standard: RS-485

Baud rate: 9600 baud

Data format: Same as RS-232

Working mode: half duplex, asynchronous

Transmission medium: twisted pair shielded two core cable, with the shielding layer connected to pin 3

Maximum cable length: 200 meters

Connection terminals: Pin 1 (RS-485+), Pin 2 (RS-485-), Pin 3 (GND)

RS-485 is suitable for environments with a distance greater than 5 meters or high interference, as its differential signal has strong anti-interference ability. The upper controller needs to have an RS-485 interface (or through an adapter).

Important: When using RS-485, RS-232 (or USS11) cannot be used simultaneously.

Communication direction control and timing

Due to RS-485 being half duplex, it is necessary to control the direction switching of transmission/reception. Direction control is achieved through the DTR signal (RS-232 standard) of the serial interface. Different controllers have different DTR processing methods:

Controller type DTR processing method

MPB needs to switch to DTR

MPR/MKS+FIS31 (old version) requires switching to DTR