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1.7.8 Memory area "timer T"
This memory area contains timer values. If timer is enabled, the value
contained into this area will increase or decrease according to the type of
timer, with the resolution chosen at the starting of timer.
1.7.9 Memory area "preset timer PT"
Memory area “preset timer PT” is the memory where preset values of
timers are stored.
1.7.10 Memory area "counters C"
This memory area contains counters values. Accordingly to the type of
counter, at each counting operation, the value contained into this area will
be updated.
1.7.11 Memory area preset values of counters PV
In this area are stored the preset values of counters PV.
1.7.12 Memory area EEPROM
EEPROM area is the non-volatile memory to store all data which cannot be
lost even if PLC is switched-off for long periods (over 6 months). Data
stored in this area is tested at the starting of the PLC to check its integrity
and in case of anomaly, the fault condition is notified (SM1.2) and the
whole area is initialized at 0 (zero). Access and writing in this area requires
longer time than any other area, therefore it is recommended not to use this
area for frequent access, but only at starting to copy the stored data , for
example in area V , and then to use these for quick access, guaranteeing a
faster program.
N.B.: EEPROM memory allows a max. number of writings for each
location (warranted 1000000), after that data integrity is no longer
assured; so it is necessary to avoid continuously writing into this
memory area.
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