EtherCAT Function Blocks that Work with SDOs
ECATReadSdo, ECATReadSdoData, ECATWriteSdo, and ECATWriteSdoData are used to work with drive
In electrical engineering, a drive is an electronic device to provide power to a motor or servo.
Control device for regulating the speed, torque and position of a motor.
A unit controlling a motor using the current and timing in its coils. or remote I/O parameters that are not supported by ML and MC function blocks A function block groups an algorithm and a set of private data.
It has inputs and outputs..
Drive or remote I/O parameters that have an associated SDO number can be read and written using these function A function calculates a result according to the current value of its inputs.
A function has no internal data and is not linked to declared instances. blocks.
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It takes more than one cycle to execute these function blocks (but less than 100 ms).
See When can I expect my SDO command to be completed? in the FAQs on how to set up the update rate for SDO communication.
Stats about the FB Execution Time
- There is a small difference in timing when running EtherCAT Ethernet ofr Control Automation Technology.
EtherCAT® is an open, high-performance Ethernet-based fieldbus system.
The development goal of EtherCAT is to apply Ethernet to automation applications which require short data update times (also called cycle times) with low communication jitter (for synchronization purposes) and low hardware costs. at 2ms compared to other frequencies.
0.25, 0.5, 1ms 2ms Mean 9ms 14ms Min 3ms 8ms Max 16ms 24ms - Max time to consider when executing a single SDO command, (i.e., before the Done output becomes TRUE): 24ms.
- Max time to consider when executing a single Drive Parameter command (i.e. before the Done output becomes TRUE): 60 ms.
4 kHz 1 kHz Mean 20 ms 11 ms Min 15 ms 9 ms Max 45 ms 58 ms - When sending multiple commands to a single drive, only one command can be sent at a time.
- The time to execute multiple commands is:
Number of commands x Execution time of a single command
- The time to execute multiple commands is:
- When commands are sent to different AKD drives at the same time, the requests do not interfere with each other.
- The function finishes execution in the same maximum time as one drive.
