Programming Precautions - Omron CQM1H - PROGRAM Programming Manual

Programming Precautions

4-6

Programming Precautions

00000 00002
00004
00001 00003
Diagram A: Not Programmable
00001 00004
00000
00000 00004
00001
Diagram B: Correct Version
Diagram A: Not Programmable for Most Instructions
25313
Diagram B: Correct Version
204
The number of conditions that can be used in series or parallel is unlimited as
long as the memory capacity of the PC is not exceeded. Therefore, use as
many conditions as required to draw a clear diagram. Although very compli-
cated diagrams can be drawn with instruction lines, there must not be any
conditions on lines running vertically between two other instruction lines. Dia-
gram A shown below, for example, is not possible, and should be drawn as
diagram B. Mnemonic code is provided for diagram B only; coding diagram A
would be impossible.
Instruction 1
Instruction 2
00002
Instruction 1
00003
Instruction 2
The number of times any particular bit can be assigned to conditions is not
limited, so use them as many times as required to simplify your program.
Often, complicated programs are the result of attempts to reduce the number
of times a bit is used.
Except for instructions for which conditions are not allowed (e.g., INTERLOCK
CLEAR and JUMP END, see below), every instruction line must also have at
least one condition on it to determine the execution condition for the instruc-
tion at the right. Again, diagram A, below, must be drawn as diagram B. If an
instruction must be continuously executed (e.g., if an output must always be
kept ON while the program is being executed), the Always ON Flag (SR
25313) in the SR area can be used.
Instruction
Instruction
Address Instruction
00000 LD
00001 AND
00002 OR
00003 AND
00004 Instruction 1
00005 LD
00006 AND
00007 OR
00008 AND NOT
00009 Instruction 2
Address Instruction
00000 LD
00001 Instruction
Section 4-6
Operands
00001
00004
00000
00002
00000
00004
00001
00003
Operands
25313