Omron SYSMAC C20P Operation Manual page 126

Converting to Mnemonic Code
TR Bits TR bits in a program are used to output (OUT) the execution condition at the
branching point and then to load back (LD) the execution condition when it is
required after returning to the branch lines. Within any one instruction block,
OUT cannot be used with the same TR address. The same TR address can,
however, be used with LD as many times as required. The following example
shows an instruction block using two TR bits. TR 1 is used in LD once; TR 0,
twice.
TR TR
0 1
0000 0001 0002
0003
0004
0005
Address Instruction
0000 LD
0001 OUT
0002 AND
0003 OUT
0004 AND
0005 OUT
0006 LD
0007 AND
0008 OUT
0009 LD
0010 AND
0011 OUT
0012 LD
0013 AND NOT
0014 OUT
If the condition assigned 0004 was not in the diagram, the second LD using
TR 0 would not be necessary because OUT with 0502 and the AND NOT
with 0005 both require the same execution condition, i.e., the execution con-
dition stored in TR 0. The diagram and mnemonic code for this program are
shown below.
Data
0000
TR 0
0001
TR 1
0002
0500
TR 1
0003
0501
TR 0
0004
0502
TR 0
0005
0503
Section 7–2
0500
0501
0502
0503
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