48
ever, 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.
0000 0001 0004 0005
0103
Block
a
Block
b
0008 0009
Block
b2
Block
b1
0002 0003
Block
a2
Block
a1
Blocks a1
and a2
Blocks b1
and b2
Blocks a
and b
Address Instruction Operands
000 LD 0000
001 AND NOT 0001
002 LD NOT 0002
003 AND 0003
004 OR LD —
005 LD 0004
006 AND 0005
007 LD 0008
008 AND 0009
009 OR LD —
010 AND LD —
011 OUT 0103
The following type of diagram can be coded easily if each block is coded in
order: first top to bottom and then left to right. In the following diagram,
blocks a and b would be combined using AND LOAD as shown above, and
then block c would be coded and a second AND LOAD would be used to
combined it with the execution condition from the first AND LOAD. Then
block d would be coded, a third AND LOAD would be used to combine the
execution condition from block d with the execution condition from the sec-
ond AND LOAD, and so on through to block n.
Block bBlock a
0100
Block nBlock c
The following diagram requires an OR LOAD followed by an AND LOAD to
code the top of the three blocks, and then two more OR LOADs to complete
the mnemonic code.
0002 0003
LR 0000
0000
0001
0004 0005
0106 0107
Address Instruction Operands
000 LD 0000
001 LD 0001
002 LD 0002
003 AND NOT 0003
004 OR LD --
005 AND LD --
006 LD NOT 0004
007 AND 0005
008 OR LD --
009 LD NOT 0106
010 AND 0107
011 OR LD --
012 OUT LR 0000
Although the program will execute as written, this diagram could be drawn as
shown below to eliminate the need for the first OR LOAD and the AND
LOAD, simplifying the program and saving memory space.
Basic Programming Section 3-4
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