WIKA MH-4-CAN Operator's manual

Special documentation
EN
Special documentation for CANopen, model MH-4-CAN
Pressure sensor, model MH-4-CAN

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WIKA special documentation, model MH-4-CAN
EN Special documentation, model MH-4-CAN Page 3 - 74
© 02/2022 WIKA Alexander Wiegand SE & Co. KG
All rights reserved. / Alle Rechte vorbehalten.
WIKA®is a registered trademark in various countries.
WIKA®ist eine geschützte Marke in verschiedenen Ländern.
Prior to starting any work, read the installation instructions!
Keep for later use!
Vor Beginn aller Arbeiten Einbauanleitung lesen!
Zum späteren Gebrauch aufbewahren!

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Contents
Contents
1. Model MH-4-CAN 6
1.1 General information . . . . . . . . . . . . . . . . . . . .6
1.2 Features . . . . . . . . . . . . . . . . . . . . . . . .6
1.3 CANopen feature summary . . . . . . . . . . . . . . . . .6
1.4 Supported bitrates . . . . . . . . . . . . . . . . . . . .6
1.5 CAN frames. . . . . . . . . . . . . . . . . . . . . . .6
2. Quick start guide 7
2.1 Quick start introduction . . . . . . . . . . . . . . . . . . .7
2.2 Connecting and powering the device . . . . . . . . . . . . . .7
2.3 Configuring the device . . . . . . . . . . . . . . . . . . .7
2.4 Starting the device . . . . . . . . . . . . . . . . . . . .8
2.5 Service Data Object (SDO) . . . . . . . . . . . . . . . . .8
2.5.1 SDO read object . . . . . . . . . . . . . . . . . . .8
2.5.2 SDO write object . . . . . . . . . . . . . . . . . . .9
3. CANopen communication 9
3.1 CANopen introduction . . . . . . . . . . . . . . . . . . .9
3.2 Device profile 404. . . . . . . . . . . . . . . . . . . . 10
3.3 Service data object (SDO) . . . . . . . . . . . . . . . . . 10
3.3.1 SDO read object . . . . . . . . . . . . . . . . . . 11
3.3.2 SDO write object . . . . . . . . . . . . . . . . . . 11
3.3.3 Abort SDO Transfer . . . . . . . . . . . . . . . . . 12
3.3.4 SDO Abort Codes . . . . . . . . . . . . . . . . . . 12
3.4 Transmit process data object (TPDO) . . . . . . . . . . . . . 13
3.4.1 TPDO mapping . . . . . . . . . . . . . . . . . . . 13
3.4.2 Changing the TPDO mapping . . . . . . . . . . . . . . 14
3.4.3 TPDO transmission types . . . . . . . . . . . . . . . 15
3.5 Network management (NMT) . . . . . . . . . . . . . . . . 16
3.5.1 Module Control Protocol . . . . . . . . . . . . . . . . 16
3.5.2 Error Control Services . . . . . . . . . . . . . . . . 17
3.5.3 Bootup Service . . . . . . . . . . . . . . . . . . . 17
3.6 Emergency object (EMCY). . . . . . . . . . . . . . . . . 17
4. The Object Dictionary 18
4.1 Object Dictionary – Communication Profile Area . . . . . . . . . 18
4.1.1 Object 1000h: Device Type . . . . . . . . . . . . . . . 18
4.1.2 Object 1001h: Error Register . . . . . . . . . . . . . . 18
4.1.3 Object 1003h: Predefined Error Field . . . . . . . . . . . 18
4.1.4 Object 1005h: COB-ID SYNC . . . . . . . . . . . . . . 20
4.1.5 Object 1008h: Manufacturer Device Name . . . . . . . . . 21

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4.1.6 Object 1009h: Manufacturer Hardware Version . . . . . . . . 21
4.1.7 Object 100Ah: Manufacturer Software Version . . . . . . . . 21
4.1.8 Object 1010h: Store Parameter Field . . . . . . . . . . . 21
4.1.9 Object 1011h: Restore Default Parameters . . . . . . . . . 23
4.1.10 Object 1014h: COB ID EMCY . . . . . . . . . . . . . . 24
4.1.11 Object 1015h: Inhibit Time Emergency . . . . . . . . . . . 25
4.1.12 Object 1017h: Producer Heartbeat Time . . . . . . . . . . 25
4.1.13 Object 1018h: Identity Object . . . . . . . . . . . . . . 25
4.1.14 Object 1800h to 1801h: Transmit PDO Communication Parameter . 27
4.1.15 Object 1A00h to 1A01h: Transmit PDO Mapping Parameter . . . . 28
4.1.16 Object 1F80h: NMT Startup . . . . . . . . . . . . . . 31
4.2 Object Dictionary – Device Profile Area . . . . . . . . . . . . 32
4.2.1 Object 6110h: AI Sensor Type . . . . . . . . . . . . . . 32
4.2.2 Object 6112h: AI Operating Mode . . . . . . . . . . . . 33
4.2.3 Object 6125h: AI Autozero . . . . . . . . . . . . . . . 34
4.2.4 Object 6126h: AI Scaling Factor . . . . . . . . . . . . . 34
4.2.5 Object 6127h: AI Scaling Offset . . . . . . . . . . . . . 35
4.2.6 Object 6130h: AI Input PV . . . . . . . . . . . . . . . 36
4.2.7 Object 6131h: AI Physical Unit PV . . . . . . . . . . . . 37
4.2.8 Object 6132h: AI Decimal Digits PV . . . . . . . . . . . . 39
4.2.9 Object 6133h: AI Interrupt Delta Input PV . . . . . . . . . . 40
4.2.10 Object 6134h: AI Interrupt Lower Limit Input PV . . . . . . . . 41
4.2.11 Object 6135h: AI AI Interrupt Upper Limit Input PV . . . . . . . 42
4.2.12 Object 6136h: AI Interrupt Hysteresis Input PV . . . . . . . . 42
4.2.13 Object 6148h: AI Span Start . . . . . . . . . . . . . . 43
4.2.14 Object 6149h: AI Span End . . . . . . . . . . . . . . . 44
4.2.15 Object 6150h: AI Status . . . . . . . . . . . . . . . . 45
4.2.16 Object 61A0h: AI Filter Type . . . . . . . . . . . . . . 47
4.2.17 Object 61A1h: AI Filter Constant . . . . . . . . . . . . . 47
4.2.18 Object 7100h: AI Input FV . . . . . . . . . . . . . . . 48
4.2.19 Object 7130h: AI Input PV . . . . . . . . . . . . . . . 49
4.2.20 Object 7133h: AI Interrupt Delta Input PV . . . . . . . . . . 50
4.2.21 Object 7134h: AI Interrupt Lower Limit Input PV . . . . . . . . 51
4.2.22 Object 7135h: AI Interrupt Upper Limit Input PV . . . . . . . . 52
4.2.23 Object 7136h: AI Interrupt Hysteresis Input PV . . . . . . . . 53
4.2.24 Object 7148h: AI Span Start . . . . . . . . . . . . . . 53
4.2.25 Object 7149h: AI Span End . . . . . . . . . . . . . . . 54
4.2.26 Object 9130h: AI Input PV . . . . . . . . . . . . . . . 55
4.2.27 Object 9133h: AI Interrupt Delta Input PV . . . . . . . . . . 56
4.2.28 Object 9134h: AI Interrupt Lower Limit Input PV . . . . . . . . 57
4.2.29 Object 9135h: AI Interrupt Upper Limit Input PV . . . . . . . . 58
4.2.30 Object 9136h: AI Interrupt Hysteresis Input PV . . . . . . . . 59
Contents

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4.2.31 Object 9148h: AI Span Start . . . . . . . . . . . . . . 60
4.2.32 Object 9149h: AI Span End . . . . . . . . . . . . . . . 61
4.3 Object Dictionary – Manufacturer Specific Area. . . . . . . . . . 62
4.3.1 Object 2010h: Measuring Range Start PV . . . . . . . . . . 62
4.3.2 Object 2011h: Measuring Range End PV . . . . . . . . . . 63
4.3.3 Object 2012h: Original Physical Unit PV . . . . . . . . . . 64
4.3.4 Object 2020h: Minimum Value PV . . . . . . . . . . . . 65
4.3.5 Object 2021h: Maximum Value PV . . . . . . . . . . . . 66
4.3.6 Object 2022h: Reset Min Max Value PV . . . . . . . . . . 67
4.3.7 Object 2023h: Damping PV . . . . . . . . . . . . . . . 68
4.3.8 Object 2320h: Node-ID . . . . . . . . . . . . . . . . 69
4.3.9 Object 2321h: Bitrate . . . . . . . . . . . . . . . . . 70
5. Emergency Object (EMCY) 70
6. References 74
7. Change log 74
Contents

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1. Model MH-4-CAN
1.1 General information
The MH-4-CAN is a pressure sensor providing measurements through a CANopen
interface implementing device profile DS404.
1.2 Features
Sample rate (pressure): 640 µs
Settling time: 2 ms
1.3 CANopen feature summary
CANopen feature summary
CANopen type NMT Slave
Bitrate From 20 kBit/s to 1 Mbit/s
Number of transmit PDOs 2
PDO Mapping Dynamic
PDO Triggering Events Synchronous, asynchronous
Heartbeat Protocol Supported
Emergency Messages Supported
Device Profile CiA 404
Layer Setting Services (LSS) Supported
Default settings
Node-ID 1
Bitrate 250 kBit/s
1.4 Supported bitrates
■1.000 kBit/s
■800 kBit/s
■500 kBit/s
■250 kBit/s
■125 kBit/s
■50 kBit/s
■20 kBit/s
■Automatic bit rate detection
1.5 CAN frames
The pressure transmitter supports standard CAN frames with 11-bit identifier. Extended
frames with 29-bit identifier are not supported but tolerated.
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2. Quick start guide
2.1 Quick start introduction
This chapter describes setting the sensor up using a simple CAN-Software without
specialized CANopen support. The sensor may be configured entirely using raw CAN
telegrams.We recommend to use a software with build-in CANopen support.
Please do note this is only a couple of possible configurations, for full details please
refer to the official CANopen specification.
2.2 Connecting and powering the device
First setup the sensor:
■Connect the CAN interface to your PC (e.g. PEAK PCAN-USB, Ixxat USB-to-
CAN) and to the sensor and start the CAN-Software (e.g. PEAK PCAN-View, Ixxat
canAnalyser3 Mini). Ensure you use the correct bitrate and Node-ID of the pressure
transmitter.
■When the MH-4 is powered up it sends a Boot-Up message
ID DLC Byte0
700h + Node-ID 1 00h
The sensor is now in PRE-OPERATIONAL mode and ready to be configured by SDO
(if necessary).
2.3 Configuring the device
The sensor is now ready to be configured and started. Choose one of the following
transmission methods:
■Acyclic synchronous transmission (transmission type = 0)
Triggered when the SYNC message is received and one of the mapped process data
has changed its value after the last transmission.
■Cyclic synchronous transmission (transmission type = 1 ... 240) (default = 1)
Triggered when a SYNC message is received (type = 1), each second SYNC
message received (type = 2), etc.
■Asynchronous event/timer triggered
■Timer triggered (transmission type = 254)
Adjustable in ms (via Object 1800h.5)
■Event triggered (transmission type = 254/255)
If the measured value falls below or exceeds an adjustable limit.
If the measured value has changed by more than a delta value compared to the
last transferred measured value.
In order to change the transmission type object 1800h.2 must be changed to the
appropriate transmission type using SDO write access (see 2.5).
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2.4 Starting the device
The configured device must now be started by the master:
■In order to send PDO-messages the sensor has to be set to OPERATIONAL mode
Master transmits:
ID DLC Byte0 Byte1
00h
(0 = all nodes)
2 01h Node-ID
The sensor is now in OPERATIONAL mode
■Depending on the previous selected transmission type the master needs to send the
SYNC object:
Master transmits:
ID DLC
80h 0
The received data now looks like (depending on configuration):
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4
180h +
Node-ID
5 6130h subindex 1 6150h
subindex 1
This data is called TPDO.
2.5 Service Data Object (SDO)
2.5.1 SDO read object
The SDO read object to read an dictionary entry:
Master transmits:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
600h +
Node-ID
8 CS =
40h
LSB MSB Subindex 00h 00h 00h 00h
Index
MH-4 CAN replies:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
580h +
Node-ID
8 CS LSB MSB Subindex LSB MSB
Index Data
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CS Number of valid bytes
4Fh 1 (Byte4)
4Bh 2 (Byte4 - Byte5)
47h 3 (Byte4 - Byte6)
43h 4 (Byte4 – Byte7)
2.5.2 SDO write object
The SDO read object to write data to an dictionary entry:
Master transmits:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
600h +
Node-ID
8 CS LSB MSB Subindex LSB MSB
Index Data
CS Number of valid bytes
2Fh 1 (Byte4)
2Bh 2 (Byte4 - Byte5)
27h 3 (Byte4 - Byte6)
23h 4 (Byte4 – Byte7)
MH-4 CAN replies:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
580h +
Node-ID
8 CS =
60h
LSB MSB Subindex 00h 00h 00h 00h
Index
Other values for CS than 60h are abort codes, indicating a failed SDO write (see 3.3).
3. CANopen communication
3.1 CANopen introduction
CANopen is a communication protocol using the CAN bus to provide sensor access and
measurements.
All CANopen data is stored in the CANopen dictionary. CANopen supports a couple of
different objects to access the object dictionary entries:
■SDO (Service Data Object): Used to access any object of the object dictionary. Offers
read and write functionality. Usually used to indentify and configure the sensor.
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■TPDO (Transmit Process Data Object): Provides status and measurement
information with a low communication overhead. Usually used to retrieve the
measured data.
The CANopen dictionary contains all data the sensor provides. It consists of multiple
entries with the following properties (in excerpts):
■Index: The 16bit object index, usually written in hexadecimal, e.g.: 1000h
■Subindex: Each object may contain up to 255 subobjects. If no subobjects are
supported a subindex of 0 is used. In case of existing subobjects subindex 0 provides
a UNSIGEND8 value indicating the number of provided subobjects.
■Data Type: The data type, e.g.: UNSIGEND32 (unsigned 32 bit integer)
■Access: The permitted dictionary access, e.g.: RW (ReadWrite), RO (Read Only)
■Default Value: The default value of an object after CANopen device initialization
■PDO Mapping: When yes the object may be transmitted by TPDO (depending on
TPDO configuration, see 3.4.1)
In the following document objects and subobjects are referenced by following
nomenclature: “object.subobject” (e.g. 1A00h.01 means object index 1A00h, subobject
01h). All indices are given as hex numbers.
CANopen devices implement different device profiles, which provide different
funktioniality and object entries.
3.2 Device profile 404
The sensor implements the CANopen devicve profile 404 for measuring devices.This
adds a couple of object dictionary entries, ranging from 6110h to 9149h.
The measurement values are called analog input process values. Mainly they are
provided through the entries 6130h, 7130h and 9130h (Analog input PV).
A couple of objects, like the analog input PV exist in 3 ways, distinguished by the fist
character:
■6xxxh The resulting data type is REAL32 (IEE 754)
■7xxxh The resulting data type is INTEGER16
■9xxxh The resulting data type is INTEGER32
Entries like these are often referred to in a form like x130h, which means ‘any kind of
analog input’
3.3 Service data object (SDO)
Service Data Objects are used to access the entries of the transmitters object dictionary.
Therefore the dictionary entries are accessed by index and subindex.
Therefore the master sends a specific request message followed by an reply from the
sensor.
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3.3.1 SDO read object
The SDO read object to read an dictionary entry:
Master transmits:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
600h +
Node-ID
8 CS =
40h
LSB MSB Subindex 00h 00h 00h 00h
Index
MH-4 CAN replies:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
580h +
Node-ID
8 CS LSB MSB Subindex LSB MSB
Index Data
CS Number of valid bytes
4Fh 1 (Byte4)
4Bh 2 (Byte4 - Byte5)
47h 3 (Byte4 - Byte6)
43h 4 (Byte4 – Byte7)
3.3.2 SDO write object
The SDO read object to write data to an dictionary entry:
Master transmits:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
600h +
Node-ID
8 CS =
60h
LSB MSB Subindex LSB MSB
Index Data
CS Number of valid bytes
2Fh 1 (Byte4)
2Bh 2 (Byte4 - Byte5)
27h 3 (Byte4 - Byte6)
23h 4 (Byte4 – Byte7)
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MH-4 CAN replies:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
580h +
Node-ID
8 CS =
60h
LSB MSB Subindex 00h 00h 00h 00h
Index
Other values for CS than 60h are abort codes, indicating a failed SDO write (see 3.3).
3.3.3 Abort SDO Transfer
If an error occurred while reading or writing an object, the transmitter answers:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
580h +
Node-ID
8 CS =
80h
LSB MSB Subindex LSB MSB
Index Abort Code
3.3.4 SDO Abort Codes
Possible SDO abort codes are:
Abort code Description
0503 0000h Toggle bit not altered
0504 0000h SDO protocol timed out
0504 0001h Client/server command specifier not valid or unknown
0504 0002h Invalid block size (block mode only)
0504 0003h Invalid block sequence number (block mode only)
0504 0004h Invalid block CRC value (block mode only)
0504 0005h Out of memory
0601 0000h Unsupported access to an object
0601 0001h Attempt to read a write only object
0601 0002h Attempt to write a read only object
0602 0000h Object does not exist in the object dictionary
0604 0041h Object cannot be mapped to the PDO
0604 0042h The number and length of the objects to be mapped would exceed PDO length
0604 0043h General parameter incompatibility reason
0604 0047h General internal incompatibility in the device
0606 0000h Access failed due to an hardware error
0607 0010h Data type does not match, length of service parameter does not match
0607 0012h Data type does not match, length of service parameter too high
0607 0013h Data type does not match, length of service parameter too low
0609 0030h Invalid value for parameter (download only)
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Abort code Description
0609 0031h Value of parameter written too high (download only)
0609 0032h Value of parameter written too low (download only)
0609 0036h Maximum value is less than minimum value
060a 0023h Resource not available: SDO connection
0800 0000h General error
0800 0020h Data cannot be transferred or stored to the application
0800 0021h Data cannot be transferred or stored to the application because of local control
0800 0022h Data cannot be transferred or stored to the application because of the present
device state
0800 0023h Object dictionary dynamic generation fails or no object dictionary is present
(e.g. object dictionary is generated from file and generation fails because of an
file error).
0800 0024h No data available
3.4 Transmit process data object (TPDO)
Transit process data objects are used by the sensor to frequently transmit measured
data with low protocol overhead. A TPDO may contain up to 8 bytes of measurement
or status data. The data mapped to the TPDO may be changed through the TPDO
mapping.
All TPDO transmission requires the sensor to be in NMT state ‘OPERATIONAL’ (see 3.4).
TPDO data is transmitted using the CAN-ID: 1800h.1 (COB-ID) + Node-ID, data length
as big as needed by the data.
3.4.1 TPDO mapping
Object entries marked as ‘mapable’ may be mapped into either TPDO.The TPDO
mapping may be accessed through the object 1A00h and 1A01h (the first one defines
the content of TPDO1 the latter of TPDO2).
Subindex 0 contains the number of used entries (up to 8, excluding subindex 0).
The other subindex contain the object dictionary entries index and subindex encoded as
a 32bit integer. The information is encoded as follows:
Bits 24..31 Bits 16..23 Bits 8..15 Bits 0..7
Index (high byte) Index (low byte) Subindex Data length in bits
Please note, that the data length needs to match the entries data size from the object
dictionary.
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Example:
the value 0x61300120 will map the object 6130h (AI input PV) subindex 01 (pressure
value as REAL32) to the PDO. Since the size of REAL32 is 32 bit, data length needs to
be set to 0x20h.
When mapping multiple entries to an TPDO, the data is mapped from subindex 1 to 8.
Example:
The PDO1 with the mapping:
1800h.0 = 2
1800h.1 = 0x61300120
1800h.2 = 0x61500108
would look like:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4
180h +
Node-ID
5 LSB MSB 6150h
subindex 1
6130h subindex 1
3.4.2 Changing the TPDO mapping
In order to change the TPDO mapping a couple of steps need to be executed in the right
order:
■Set TPDO invalid by switching bit 31 in the COB-ID (e.g. 1800h.1)
■Set TPDO mapping invalid by setting the mapping index (e.g. 1A00h.0) to 0
■Change TPDO mapping entries
■Set TPDO mapping index top number of used entries
■Set TPDO valid by switching bit 31 back.
Example:
■Set TPDO invalid by setting bit “valid” to 1b (1800h.1)
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
601h 8 23h 00h 18h 01h 81h 01h 00h C0h
Index Data
■Disable mapping by setting index 1A00.0 to 00h
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
601h 8 2Fh 00h 1Ah 00h 00h 00h 00h 00h
Index Data
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3. CANopen communication
■Modify mapping by changing the values of the corresponding sub-indices, e.g.
change mapped object to 6130.1
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
601h 8 23h 00h 1Ah 01h 20h 01h 30h 61h
Index Data
■Enable mapping by setting sub-index 00h to the number of mapped objects (1).
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
601h 8 2Fh 00h 1Ah 00h 01h 00h 00h 00h
Index Data
■Set TPDO valid by setting bit “valid” to 0b (1800.1)
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
601h 8 23h 00h 18h 01h 81h 01h 00h 40h
Index Data
3.4.3 TPDO transmission types
The PDO transmission types can be configured via objects 1800h/1801h subindex 2.
Synchronous transmission (cyclic, acyclic)
A transmission type of 0 means that the PDO is triggered acyclic when a SYNC
message is received and one of the mapped process data has changed its value after
the last transmission.
A transmission type of n (1 … 240) means that the PDO is triggered cyclic with every
n-th SYNC message.
Asynchronous transmission
A transmission type of 254 means that the PDO is triggered after the event timer
elapses.The event timer can be configured via objects 1800h/1801h subindex 5.
A transmission type of 254/255 means that the message will be sent if the measured
value falls below or exceeds an adjustable limit and also if the measured value has
changed by more than a delta value compared to the last transferred measured value.
The interrupt limits can be configured via entries x133h/x134h/x135h/x136h.

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3.5 Network management (NMT)
Every CANopen device has an internal state machine as shown in figure 1:
NMT State machine (simplified):
After POR all devices enter the state ‘INITIALISING’. The initial state is left automatically
after finishing the initialization. Leaving the initialization state is indicated by sending the
bootup message (see 3.2).
After leaving ‘INITIALISING’the device entered the Pre-Operational state. The
PRE-OPERATIONAL is a kind of idle state, this is the goto state to configure the device.
In order to obtain TPDOs from the sensor, the sensor must be started via NMT
command from the master (See 3.5.1)).
It is possible to configure the sensor to enter the state Operational without NMT
command, for more information please refer to 4.1.16 (Object 1F80h).
In case of an EMCY the device stays in its current state.
3.5.1 Module Control Protocol
NMT Master request:
ID DLC Byte0 Byte1
00h 2 CS Node-ID (0 = all nodes)
Power on or POR
INITIALISING
PRE-Operational
STOPPED
OPERATIONAL
Reset Boot up message
NMT_Start
NMT_PreOperational
NMT_PreOperational
Reset
NMT_Stop
NMT_Start
NMT_Stop
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3. CANopen communication
CS: NMT command specifier
NMT services are unconfirmed.
CS
01h Start Remote Node
02h Stop Remote Node
80h Enter Pre-Operational
81h Reset Node
82h Reset Communication
3.5.2 Error Control Services
Through Error control services the NMT detects failures in a CAN-based.
The heartbeat mechanism for a device is established through cyclically transmitting a
message by a heartbeat producer. One or more devices in the network are aware of
this heartbeat message. If the heartbeat cycle fails for the heartbeat producer the local
application on the heartbeat consumer will be informed about that event.
(see 4.1.12 (object heartbeat producer)).
3.5.3 Bootup Service
Through this service, the NMT slave indicates that a local state transition occurred from
the state ‘INITIALISING’ to the state ‘PRE-OPERATIONAL’. The protocol uses the same
identifier as the error control protocols.
ID DLC Byte0
700h + Node-ID 1 00h
3.6 Emergency object (EMCY)
In case of an EMCY the sensor sends an EMCY object:
Sensor transmits:
ID DLC Byte0 Byte1 Byte2 Byte3 Byte4 Byte5 Byte6 Byte7
80h +
Node-ID
8 LSB MSB Error
register
(1001h)
Subindex Manufacturer specific error field
Emergency
Error Code
For detailed error behaviour description and supported error codes please refer to
chapter 5.

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4. The Object Dictionary
4.1 Object Dictionary – Communication Profile Area
4.1.1 Object 1000h: Device Type
The device type describes the type of device and its functionality. The lower 16-bit field
describes the device profile number (404) an the upper 16-bit field contains additional
information (analogue input block, Manufacturer-specific PDO Mapping).
Index 1000h
Parameter Name Device Type
Object Type VAR
Data Type UNSIGNED32
Access ro
Default Value 0x00820194
PDO Mapping No
4.1.2 Object 1001h: Error Register
The error register is a field of 8 bits, each for a certain error type. If an error occurs the
corresponding bit is set.
Supported error bits:
■Bit 0: Generic Error (always set at any error situation)
■Bit 3: Temperature
■Bit 5: Device profile specific, always 0b for DS 404
■Bit 4: Communication error (overrun, error state)
■Bit 7: Manufacture specific
The detailed information of each error is described in 6 Emergency Object (EMCY)
Index 1001h
Parameter Name Error Register
Object Type VAR
Data Type UNSIGNED8
Access ro
PDO Mapping No
4.1.3 Object 1003h: Predefined Error Field
This object holds errors that have occurred on the transmitter and have been signalled
via Emergency Object. It represents an error history containing up to 4 errors. For a list
of possible error entries please refer to chapter 5.
4. The Object Dictionary

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4. The Object Dictionary
In case that any error is into the history the values have the following meaning:
For detailed description of Error code see 6 Emergency Object (EMCY).
The Bits 16 to 23 (1 Byte) is Byte 4 in the EMCY message
The Bits 24 to 31 (1 Byte) is Byte 3 in the EMCY message
Writing to sub index 0 deletes the entire error history.
Index 1003h
Parameter Name Predefined Error Field
Object Type ARRAY
Sub-Index 0
Parameter Name Number of Errors
Object Type VAR
Data Type UNSIGNED8
Access rw
Default Value 0
PDO Mapping No
Sub-Index 1
Parameter Name Standard Error Field
Object Type VAR
Data Type UNSIGNED32
Access ro
Default Value 0
PDO Mapping No

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Sub-Index 2
Parameter Name Standard Error Field_2
Object Type VAR
Data Type UNSIGNED32
Access ro
Default Value 0
PDO Mapping No
Sub-Index 3
Parameter Name Standard Error Field_3
Object Type VAR
Data Type UNSIGNED32
Access ro
Default Value 0
PDO Mapping No
Sub-Index 4
Parameter Name Standard Error Field_4
Object Type VAR
Data Type UNSIGNED32
Access ro
Default Value 0
PDO Mapping No
4.1.4 Object 1005h: COB-ID SYNC
COB-ID of the Synchronization object.
Index 1005h
Parameter Name COB ID SYNC
Object Type VAR
Data Type UNSIGNED32
Lower Limit 0x00000001
Access rw
Default Value 0x00000080
PDO Mapping No
4. The Object Dictionary