Schneider Electric DS301 manual Synchronization, Sync message

Models: DS301

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3 Basics

IL•1F CANopen DS301

3.5Synchronization

The synchronization object SYNC controls the synchronous exchange of messages between network devices for purposes such as the simul- taneous start of multiple drives.

The data exchange conforms to the producer-consumer relationship. The SYNC object is transmitted to all devices by a network device and can be evaluated by all devices that support synchronous PDOs.

SYNC-Consumer

SYNC-Consumer

COB-ID

 

 

CAN

SYNC- Producer

SYNC-Consumer

Figure 3.25 SYNC message

Time values for synchronization Two time values define the behavior of synchronous data transmission:

The cycle time specifies the time intervals between 2 SYNC mes- sages. It is set with the object Communication cycle period(1006h).

The synchronous time window specifies the time span during which the synchronous PDO messages must be received and trnasmitted. The time window is defined with the object Synchronous window length (1007h).

 

SYNC

T_PDO (status)

CAN-Bus

R_PDO (controller)

 

SYNC

 

synchronous

process

time window

R_PDO data

cycle time

 

Figure 3.26 Synchronization times

Synchronous data transmission From the perspective of a SYNC recipient, in one time window the status data is transmitted first in a T_PDO, then new control data is received via an R_PDO. However, the control data is only processed when the next SYNC message is received. The SYNC object itself does not transmit data.

0198441113586, V2.01, 11.2008

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Fieldbus interface

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Schneider Electric DS301 manual Synchronization, Sync message