Function Block Programming; Block Type And The Fbd Base - Mitsubishi Electric a2 Series Programming Manual

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2 Simple Application Controllers
2.

Function Block Programming

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The 2 Series Controller is programmed with a user-friendly method of combining special-
purpose dedicated function blocks. The task is broken down into various stages which can be
represented by a number of function blocks. Function Block Programming simplifies
application representation but ensures complete process control. The program can be
developed in very simple steps but even a complex task can be represented in this way. For
ease of use, the function blocks have been preprogrammed to perform certain tasks yet offer
flexibility to be tailored to individual requirements.
Figure 1.1: Principle of Function Block Programming
The user can build a complex circuit in small, easy steps by starting at the input and working
forward in a logical manner. The
necessary control for the application according to the system algorithm. Each function block
provides specific control parameters, accessible by the user, to tailor each program for
complete application suitability. The function blocks are connected together to form a circuit
using the Function Block Diagram (FBD.)
2.1

Block Type and the FBD base

There are seven sets of items that can be used in the function block program: Inputs, Front
Panel Keys, System Memory Bits, Logic Blocks, Function Blocks, User-defined Function
Blocks and Outputs. A brief description of each follows.
I01
1 B002
I02
2
OR
3
I03
4
I0n - Input n
O0n - Output n
OR - OR Boolean Function Block
SR - Set/Reset Function Block
OS - One Shot Function Block
B001
S
OS
C
One Shot
B003
S
SR
R
Set/Reset
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2 will gather and process information and provide the
Function Block Programming 2
O01
O02
O03
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