SMC Networks LECSB Series, Руководство по эксплуатации

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13 - 10
13. COMMUNICATION FUNCTION
13.3.7 Initialization
After the slave station is switched on, it cannot reply to communication until the internal initialization processing
terminates. Hence, at power-on, ordinary communication should be started after.
(1) 1s or longer time has elapsed after the slave station is switched on; and
(2) Making sure that normal communication can be made by reading the parameter or other data which does
not pose any safety problems.
13.3.8 Communication procedure example
The following example reads the set value of alarm history (last alarm) from the driver of station 0.
Data item Value Description
Station number 0 Driver station 0
Command 33 Read command
Data No. 10 Alarm history (last alarm)
Checksum 30H 33H 33H 02H 31H 30H 03H FCH
1 0 STX ETX 3 3
Yes
No
Yes
No
No
No
Yes
Yes
Yes
No
[0][3][3] [1][0]
[0]
Axis No. Command
Data No.
Data
Start
Data make-up
Checksum calculation and
addition
Addition of SOH to make
up transmission data
Data transmission
Data receive
Is there receive data?
3 consecutive times?
Error processing
Other than error code
[A] [a]?
Receive data analysis
End
300ms elapsed?
3 consecutive times?
Error processing
100ms after EOT transmission
STX ETX
46H 43H SOH F C Transmission data 3 3 STX 1 0 ETX
Master station slave station
Master station slave station
Master station slave station
0