Ml1400 s:40 and s:41

THE S:40 for the "hour" and S:41 for "minute" are not updating, and do not show on the processor status main tab.
does the ML1400 has a real clock? if yes, how to get it to enable or update?

Thanks

i saw an example of an RTC, so i used it instead of s:40 and s:41. i do not know if the RTC stops on its own while processor running or not.

Using RSLogix 500, Under the Controller organizer click on Function Files and the RTC tab. There is a button to set the clock to your PC time. Out of the box, the ML1400 RTC is disabled with zeroes in the registers. Not sure, but that might be done to extend the life of the RTC battery.

The Micrologix doesn't use S:37 thru S:42, but the SLC does. So RSLogix 500 will use the default comments for those addresses which can be misleading if the program is not for a SLC.

The RTC Function file addresses are integers that can be read and written by PLC logic in much the same way as the S registers in a SLC.

The address format is:
RTC:0.YR
RTC:0.MON
RTC:0.DAY
RTC:0.HR
RTC:0.MIN
RTC:0.SEC
RTC:0.DOW (Day of week)

At least the first 6 are in a contiguous block (I never use the DOW). So, it is possible to copy another group of integers into them. You have to use the CPW instruction to get it to verify in a Micrologix rather than the normal COP instruction.