KEYENCE IV Series - Manual (Page 48)

3-26 - IV Series User’s Manual (Field Network) -
Operating procedure of the cyclic communication
This section explains the method for communicating from the PLC to the IV series using cyclic communication.
Reading out the overall status result of the IV series
(Handshake control [Disabled])
z „
When a trigger is successful
Trigger request
Result of A
A B
A B
A B
A
A B
A
B
B
Result of B
Trigger response
BUSY
Imaging status
Result update complete
Result available
Result No.
Overall judgment
(1) Execute a [Trigger request]. (0 → 1)
(2) If the trigger is valid, [Trigger response] will change from 0 to 1.
(3) [BUSY] will change from 0 to 1 when a trigger is input.
(4) [BUSY] will change from 1 to 0 when the judgment process ends.
The [Result update complete] Bit will be switched at this time; and [Overall judgment] will be updated.
y [Result update complete] will switch to “1” if its value was “0” after the previous judgment update (or
from “0” to “1” if the previous value was “1”).
y [Result available] will switch from 0 to 1 at the timing when the first judgment process has been
confirmed; and the new value will be retained thereafter.
y [Result available] will be reset in the following conditions:
y If handshake control is set to [Disabled]
- When the program is switched
- When the unit’s status is switched from “Setting” to “RUN”
- When a buffer clear request is issued
y If handshake control is set to [Enabled]
- When a buffer clear request is issued
y [Result No.] will be counted up each time the status result is updated. The upper limit value is 32767. If
the maximum value is exceeded, it will go back to 0 and start counting up again.
y [Result No.] will also count the judgment process counts that were skipped due to the cyclic frequency
setting.
y [Busy] and [Imaging] may be skipped in some cyclic frequency settings. It is therefore necessary to take
the imaging condition into consideration when setting the cyclic frequency.
Operating procedure of the cyclic communication
3
Cyclic communication