Service data communication – Baumer GNAMG User Manual

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Baumer IVO GmbH & Co. KG

21.11.12

Villingen-Schwenningen, Germany

3.3.3. Service data communication

Service data objects are conform to CiA standards. A certain object is accessed by index and subindex. There
are data requests or, if required, data are written into the object.

General information on SDOs
SDO telegram structure
:

COB-ID

DLC

Command

Object L

Object H Subindex Data 0 Data 1 Data 2 Data 3


A SDO-COB-ID is composed as follows:
Master -> inclination sensor : 600h + Node-ID
Inclination sensor -> master : 580h + Node-ID

DLC (Data length code) defines the length of a telegram with following structure:
1 byte command + 2 bytes object + 1 byte subindex + number of data bytes (0..4).

The command byte specifies whether data are write or read only and how many data bytes are involved:

SDO command

Meaning

Data length

22h

Download Request

max. 4 Byte

transmit parameter to inclination sensor

23h

Download Request

4 Byte

2Bh

Download Request

2 Byte

2Fh

Download Request

1 Byte

60h

Download Response

-

confirm download to master

40h

Upload Request

-

request parameter upload from inclination
sensor

42h

Upload Response

max. 4 Byte

parameter to master, max. 4 bytes

43h

Upload Response

4 Byte

4Bh

Upload Response

2 Byte

4Fh

Upload Response

1 Byte

80h

Abort Message

-

Inclination sensor gives error code to
master


Abort Message means an error in CAN communication. SDO command byte is 80h. Object and subindex are
those of the requested objects. The error code is in bytes 5..8.

ID

DLC

Byte 1

Byte 2

Byte 3

Byte 4

Byte 5

Byte 6

Byte 7

Byte 8

580h + Node-ID 8

80h

Object L Object H Subindex ErrByte 0 ErrByte 1 ErrByte 2 ErrByte 3


Byte 8..5 composes the SDO abort message (Byte 8 = MSB).
The following messages are supported:

05040001h

: command byte not supported

06010000h

: incorrect access to an object

06010001h

: Read access to write only

06010002h

: Write access to read only

06020000h

: Object not supported

06090011h

: Subindex not supported

06090030h

: Value is not within the defined limits

06090031h

: Value too high

08000000h

: General error

08000020h

: Incorrect memory signature ("save")

08000021h

: No data saving possible

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