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15. COMMUNICATION FUNCTION
15.3.7 Initialization
After the slave station is switched on, it cannot reply to c ommunication until the internal initialization processing
terminates. Hence, at power-on, ordinary comm unication should be started after.
(1) 1s or more time has elapsed after the slave s tation is switched on; and
(2) Making sure that normal communication ca n be made by reading the parameter or other data which does
not pose any safety problems.
15.3.8 Communication procedure example
The following example reads the set value of a larm history (last alarm) from the servo amplif ier of station 0.
Data item Value Description
Station number 0 Servo amplifier station 0
Command 33 Read command
Data No. 10 Alarm history (last alarm)
Checksum 30H 33H 33H 02H 31H 30H 03H FCH
1 0STX ETX3
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 a nd
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 FC
Transmission data 3
3STX 10ETX
Master station slave station
Master station slave station
Master station slave station
0