SEW EURODRIVE DFP21B bus interface

4.2 MOVITRAC ®  B (Gateway Mode)

P100=SBus (Setpoint Source)

P101=SBus (control signal source)

P813 (SBus address): Set to 1-8 (cannot use 0 due to gateway occupancy)

P815 (SBus timeout): Recommended 50-200 ms

Terminal Enable: DI1 (CW/stop) is connected to+24V, and the remaining terminals are set to "No Function"

Loop process data and parameter channel

5.1 Process Data Exchange

The DP master station sends control words, speed settings, ramp time, etc. through process output data (PO); The frequency converter returns status words, actual speed, current, etc. through process input data (PI). In SIMATIC S7:

1-2 PD words can be directly accessed using the L/T instruction.

≥ 3 PD words must use SFC14 (DPRD_DAT) and SFC15 (DPWR_daT) to ensure data consistency.

5.2 8-byte MOVILINK ®  Parameter channel structure

The parameter channel is located before the process data (when "Param+x PD" is configured), and its structure is as follows:

Byte name description

0 Management service identifier, data length, handshake bit, status bit

1 Subindex reserved, must be 0x00

2 Index high parameter index high byte

3 Index low parameter index low byte

4-7 Data 4-byte data (MSB in byte 4, LSB in byte 7)

Definition of Byte 0 bits for management:

Position 0~3: Service identifier (0001=READ, 0010=WRITE)

Bit 4-5: Data length (11=4 bytes, must be set to 3)

Position 6: Handshake position (needs to be flipped every time a new task is created)

Bit 7: Status bit (0=Success, 1=Error)

5.3 READ Service Execution Steps

Set index (byte2-3).

Set the management byte to 0x01 or 0x41 (for READ service only, regardless of data length).

Changing the handshake position (such as from 0 to 1) triggers the service.

Wait for the handshake position returned by the frequency converter to match the sent value.

Read data values from bytes 4-7.

If the status bit is 1, then byte4-7 is the return code (error class, error code, additional code).

5.4 WRITE Service Execution Steps

Set the index and data values (byte4-7).

Set management byte: Service identifier 0010 (WRITE), data length 11 (4 bytes), handshake bit flip, status bit=0 → typical value 0x32 or 0x72.

Trigger service (handshake position change).

Waiting for confirmation. If the status bit is 0, the write is successful; If=1, return an error code.

Data format: All parameter values are 4 bytes, aligned to the right (LSB in byte 7). For detailed data scope, please refer to "MOVIDRIVE ®  Parameter List ".

5.5 Return Code (Error Diagnosis)

When WRITE or READ fails, byte4-7 returns the following information:

Byte content

4 Error classes

5 Error codes

6-7 Additional code

Common Additional Codes (SEW Specific):

0x0810: Illegal parameter index

0x0811: Function/parameter not implemented

0x0812: Read only

0x0813: Parameter lock activated

0x0815: Parameter value too large

0x0816: Parameter value too small

0x0817: Required option card not installed

0x081C: Controller Inhibit Required

0x081D: Invalid parameter value

Special error:

Service identifier encoding error → Error class 0x05, error code 0x05

The data length is not 4 bytes → Error class 0x06, error code 0x08

Internal communication error → Error class 0x06, error code 0x02 (recommended to power off and restart)

Detailed explanation of PROFIBUS DP-V1 function

6.1 Basic Concepts of DP-V1

PROFIBUS DP-V1 adds a non cyclic READ/WRITE service on the basis of standard DP, allowing the transmission of large amounts of parameter data without affecting the cyclic process data cycle. Main roles:

C1 main station (such as PLC): responsible for cyclic data exchange, and can also initiate non cyclic parameter requests.

C2 main station (such as PC, HMI): only performs non cyclic communication and supports multiple parallel connections.

6.2 Dataset 47 (DS47)

The SEW drive device uses dataset 47 as the DP-V1 parameter channel. Its structure supports two access modes:

MOVILINK ®  Service (Request ID=0x40): capable of executing read, write, write volatile (write only to RAM), etc.

PROFIdrive service (Request ID=0x01 Request parameter, 0x02 Change parameter): Compliant with PROFIdrive specification V3.1.

Key elements of dataset 47:

Request reference: Used to match requests and responses.

Request ID/Response ID: Identify the service type and positive or negative response.

Axis: Used for addressing in multi axis systems (MOVIDRIVE) ®  Fixed at 0).

No. of parameters: usually 1.

Attribute: For MOVILINK ®， The upper half byte is the service identifier (0x1=Read, 0x2=Write, 0x3=Write volatile).

Parameter number: OVILINK parameter index.

Subindex: Always 0.

Format: 0x43 (two characters), 0x44 (error).

No. of values: usually 1.

Value/Error value: Data or error code.

6.3 DP-V1 Communication Timing

The master station sends a Write. req (DS47) to write the parameter request to the slave station.

Processing requests from the slave station (which may take several milliseconds).

The main station sends READ.req query responses periodically.

If the slave station returns error code 0xB5 (status conflict), it indicates that it has not been processed yet, and the master station needs to repeat READ until a positive response is received.

When responding positively, READ.res contains parameter values or write confirmations.