Schneider Electric DS301 manual Service data communication, Overview, SDO data exchange

Page 26

3 Basics

IL•1F CANopen DS301

3.3Service data communication

3.3.1Overview

Service Data Object(SDO: Service Data Object) can be used to access the entries of an object dictionary via index and subindex. The values of the objects can be read and, if permissible, also be changed.

Every network device has at least one server SDO to be able to respond to read and write requests from a different device. A client SDO is only required to request SDO messages from the object dictionary of a dif- ferent device or to change them there.

The T_SDO of an SDO client is used to send the request for data ex- change; the R_SDO is used to receive. The data frame of an SDO con- sist of 8 bytes.

SDOs have a higher COB ID than PDOs and therefore are sent over the

CAN bus at a lower priority.

3.3.2SDO data exchange

A service data object (SDO) sends parameter data between two de- vices. The data exchange conforms to the client-server relationship. The server is the device to whose object dictionary an SDO message refers.

Client
R_SDO T_SDO
	(request)
	COB-ID	data
CAN	data
COB-ID	data
(response)		T_SDO R_SDO
		T_SDO R_SDO
		Server

Figure 3.10 SDO message exchange with request and response

Message types Client-server communication is triggered by the client to send parameter values to the server or to get them from the server. In both cases, the cli- ent starts the communication with a request and receives a response from the server.

0198441113586, V2.01, 11.2008

26	Fieldbus interface

Image 26

Contents IL1F CANopen DS301 Important information Table of Contents Table of Contents IL1F CANopen DS301 Object directory Table of Contents IL1F CANopen DS301 Writing conventions and symbols Writing conventions and symbols IL1F CANopen DS301 CAN-Bus IntroductionAbout this manual Operating modes and functions in fieldbus mode Fieldbus devices networked via can busDocumentation and literature references Can users and manufacturers organizationIntroduction IL1F CANopen DS301 Before you begin safety information Before you begin safety information IL1F CANopen DS301 CANopen description language BasicsCANopen technology Communication layersObjects Index hex Object groups Supported By the driveIL1F CANopen DS301 Basics CANopen profiles CANopen reference modelIndex Subindex Object Meaning Communication profileObject dictionary Index range Object groups Supported Hex By the drive Communication objects Communication objectsCOB ID with function code and node address TPDO4 Communication relationships Master slave relationshipsClient-server relationship SDO data exchange Service data communicationOverview SDO message 11 SDO message, exampleReading and writing data Message type Data length used Bytes14 Reading a parameter value Message type Data length used Byte Bytes15 Response with error message error response Process data communication PDO data exchange 16 PDO data exchangeUINT32 Dynamic and static PDO mapping 18 Requesting a message with RTR =Receive PDO RPDO4 master slave Structure of RPDO4State machine drivectrl Operating modes modeCtrl JOG@ Warning Transmit PDO TPDO4 product to masterStructure of TPDO4 20 Structure of TPDO4Handshake with Mode Toggle Bit Bit Name Description22 Mode Toggle Handshake, short movement Master Slave XendBasics IL1F CANopen DS301 Emergency service 23 Error message with the Emcy objectSynchronization 25 Sync message27 Cyclic and acyclic transmission Network management services NMT services for device controlPersistent data memory NMT service Transition MeaningInitialization Node/Life guarding NMT services for connection monitoringCommand Specifier NMT service Transition 31 Acknowledgement of the NMT slave 32 Node Guarding and Life Guarding with time intervals Installation Installation IL1F CANopen DS301 Commissioning Commissioning the deviceCommissioning the fieldbus network Starting fieldbus modeAddress and baud rate Troubleshooting Error Error class Cause of error TroubleshootingSelecting the CANopen master SyCon CANopen configuration softwareCreating a new network Setting the bus parameters Selecting and inserting nodes Operation OverviewOperation IL1F CANopen DS301 Transmit data Using SDO commandsWriting parameters Receive dataIndex Sub Data Description Synchronous errorsReading a parameter Bit no Value Meaning Operating Name Power Description State StageChanging operating states with PDO4 Example Switching the power stage on and offTriggering a Quick Stop Come to a standstill System is to resume opera Resetting faults Examples for the operating modes with PDO4 Operating mode Profile Position absolute positioning Operating mode Profile Position relative positioning Operating mode Profile VelocityPosition setting Master --- SlaveOperating mode Homing Error signaling via PDO4 Asynchronous errorsPositioning running xerr=0 Operation IL1F CANopen DS301 Diagnostics and troubleshooting Fieldbus communication error diagnosticsMessages on the device status Error diagnostics via fieldbusMessage objects Error code table CANopen error messagesError register Bit Message MeaningSDO error message Abort Error code MeaningObject code Meaning Coding Specifications for the objectsObject directory Data type Value range Data lengthIndex Subindex Designation Obj. code Data type Access Objects, overviewDevice type Error registerObjects of the product Manufacturer device name Bit coding, subindex 00h1008h 100ChIndex 100D h Object name Life time factor Object code Index 1018 h Object name Identity Object Object code Data type PDO Communication parameter Bit coding, subindex 02h Bit assignment subindex 01hBit 30 RTR bit Bit Acces Value Meaning1603h Receive PDO4 mapping Value description 1803h Transmit PDO4 communication parameter BitMeaningSubindex 03 h, inhibit time TPDO4 Meaning IL1F CANopen DS301 Object directory PDO4 mapping 1603h Glossary Units and conversion tablesTorque TemperatureRotation Moment of inertiaDefault value Factory setting Terms and AbbreviationsPower amplifier See power stage Index CanIndex IL1F CANopen DS301 IL1F CANopen DS301 Index NMT IL1F CANopen DS301 Index 102 Fieldbus interface