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ifm
Programming Manual (supplement) CAN module RTC CR3020
2017-10-26
ifm function elements
ifm functional elements, POUs (Classic)
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3.3.6
RTC_REQUEST_ALARM
21893
Unit type = function block (FB)
Unit is contained in the library
ifm_RTC_Classicx_V01yyzz.LIB
(x = 1...n = number of the CAN interface (depending on the device,
→ data sheet))
Symbol in CODESYS:
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Description
21886
RTC_REQUEST_ALARM requests the real-time clock (RTC) for the following current values:
• the remaining time till the setting of the alarm output
• the current node ID
With the identifier (0x400 + node ID), the controller sends an empty message (without data) to the bus
in order to request the current data.
The real-time clock responds to this with the identifier (0x380 + node ID).
For this, the real-time clock sends a matrix with the following content:
remaining days, hours and minutes as well as the current node ID
The function assigns this data to the corresponding output parameters.
The output parameter RESULT informs about the current operating status of the POU.
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Parameters of the inputs
21881
Parameter
Data type
Description
INIT
BOOL
TRUE (only for 1 cycle):
Function block is initialised
FALSE:
during further processing of the program
REQUEST
BOOL
TRUE:
execute this function element
Request data
FALSE:
unit is not executed
NODE_ID
BYTE
Node number of the addressed CAN participant