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Sequence Input Instructions Section 3-3
Using TR0 to TR15 TR0 to TR15 are used only with LOAD and OUTPUT instructions. There are
no restrictions on the order in which the bit addresses are used.
Sometimes it is possible to simplify a program by rewriting it so that TR bits
are not required. The following diagram shows one case in which a TR bit is
unnecessary and one in which a TR bit is required.
In instruction block (1), the ON/OFF status at point A is the same as for output
CIO 00200, so AND 000001 and OUT 000201 can be coded without requiring
a TR bit. In instruction block (2), the status of the branching point and that of
output CIO 000202 are not necessarily the same, so a TR bit must be used. In
this case, the number of steps in the program could be reduced by using
instruction block (1) in place of instruction block (2).
TR0 to TR15
Considerations
TR bits are used only for retaining (OUT TR0 to TR15) and restoring (LD TR0
to TR15) the ON/OFF status of branching points in programs with many out-
put branches. They are thus different from general bits, and cannot be used
with AND or OR instructions, or with instructions that include NOT.
000000 LD 000000
000001 OUT TR0
000002 AND 000001
000003 OUT TR1
000004 AND 000002
000005 OUT 000500
000006 LD TR1
000007 AND 000003
000008 OUT 000501
000009 LD TR0
000010 AND 000004
000011 OUT 000502
000012 LD TR0
000013 AND NOT 000005
000014 OUT 000503
Instruction OperandsAddress
(1)
(2)
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