Omron SYSMAC CV Series Operation Manual page 96

Mnemonic Code
0000 0000
00 01
Block
a
Complicated Diagrams
Block
a1
0000 0000 0000
00 01 04
0000 0000 0000
02 03 06
Block
a2
Block
a
84
Although the following diagram is similar to the one above, block b in the diagram
below cannot be coded without separating it into two blocks combined with OR
LOAD. In this example, the three blocks have been coded first and then OR
LOAD has been used to combine the last two blocks followed by AND LOAD to
combine the execution condition produced by the OR LOAD with the execution
condition of block a.
When coding the logic block instructions together at the end of the logic blocks
they are combining, they must, as shown below, be coded in reverse order, i.e.,
the logic block instruction for the last two blocks is coded first, followed by the
one to combine the execution condition resulting from the first logic block
instruction and the execution condition of the logic block third from the end, and
on back to the first logic block that is being combined.
Block
b1
0000 0000
02 03
0000 0002
04 02
Block
b2
Block
b
When determining what logic block instructions will be required to code a dia-
gram, it is sometimes necessary to break the diagram into large blocks and then
continue breaking the large blocks down until logic blocks that can be coded
without logic block instructions have been formed. These blocks are then coded,
combining the small blocks first, and then combining the larger blocks. Either
AND LOAD or OR LOAD is used to combine the blocks, i.e., AND LOAD or OR
LOAD always combines the last two execution conditions that existed, regard-
less of whether the execution conditions resulted from a single condition, from
logic blocks, or from previous logic block instructions.
When working with complicated diagrams, blocks will ultimately be coded start-
ing at the top left and moving down before moving across. This will generally
mean that, when there might be a choice, OR LOAD will be coded before AND
LOAD.
The following diagram must be broken down into two blocks and each of these
then broken into two blocks before it can be coded. As shown below, blocks a
and b require an AND LOAD. Before AND LOAD can be used, however, OR
LOAD must be used to combine the top and bottom blocks on both sides, i.e., to
combine a1 and a2; b1 and b2.
Block
b1
0000
05
0002
07
Block
b2
Block
b
Address Instruction Operands
00000
0005
02
00001
00002
00003
00004
00005
00006
00007
00008
Address Instruction Operands
0005
00000 LD
03
00001 AND NOT
00002 LD NOT
00003 AND
00004 OR LD
00005 LD
00006 AND
00007 LD
00008 AND
00009 OR LD
00010 AND LD
00011 OUT
Section 4-4
LD NOT 000000
AND 000001
LD 000002
AND NOT 000003
LD NOT 000004
AND 000202
OR LD —
AND LD —
OUT 000502
000000
000001
000002
000003
—
Blocks a1 and a2
000004
000005
000006
000007
— Blocks b1 and b2
—
Blocks a and b
000503