Input Process Image:The Processor scans all the input points from

base as well as expansions in input scan & stores the status in input process image.

%IB0 to %IB31 Output Process Image:The processor updates the status of output

points as per the logic scan & stores the updated status in the output process image.

%IB0 to %IB31

Marker Memory Marker memory holds the intermediate

results in the application program. This is addressable global memory.

%MB0 to %MB3999 Data MemoryData memory holds the intermediate results

and function block instance data. This is memory is addressed by user defined symbolic name.

Addressing of Symbols:-

----||----- NO NORMALLY OPEN

----|\|---- NC NORMALLY CLOSED

----( )---- OP O/P COIL ----( R )---- RESET O/P RESET ----( S )---- SET O/P SET

Types Of Timer:1. TON - On delay Timer 2. TOFF - Off Delay Timer3. TP - Pulse Timer No. of Timers-: Unlimited Max Preset Value-: Around 24

days

Types of Counter:1. CTU: Counter Up2. CTD: Counter Down3. CTUD : Counter Up Down Max No. of Counters: Unlimited Max Preset Value: 32767