565
Appendix B
Error and Arithmetic Flag Operation
The following table shows the instructions that affect the ER, CY, GT, LT and EQ flags. In general, ER indicates that
operand data is not within requirements. CY indicates arithmetic or data shift results. GT indicates that a compared
value is larger than some standard, LT that it is smaller, and EQ, that it is the same. EQ also indicates a result of
zero for arithmetic operations. Refer to
Section 7 Instruction Set
for details.
Vertical arrows in the table indicate the flags that are turned ON and OFF according to the result of the instruction.
Although ladder diagram instructions,TIM, and CNT are executed when ER is ON, other instructions with a vertical
arrow under the ER column are not executed if ER is ON. All of the other flags in the following table will also not
operate when ER is ON.
Instructions not shown do not affect any of the flags in the table. Although only the non-differentiated form of each
instruction is shown, differentiated instructions affect flags in exactly the same way.
The ER, CY, GT, LT and EQ Flags are turned OFF when END(01) is executed, so their status cannot be monitored
with a Programming Device.
The status of the ER, CY, GT, LT and EQ Flags is affected by instruction execution and will change each time an
instruction that affects them is executed. Differentiated instructions are executed only once when their execution
condition changes (ON to OFF or OFF to ON) and are not executed again until the next specified change in their
execution condition. The status of the ER, CY, GT, LT and EQ Flags is thus affected by a differentiated instruction
only when the execution condition changes and is not affected during scans when the instruction is not executed,
i.e., when the specified change does not occur in the execution condition. When a differentiated instruction is not
executed, the status of the ER, CY, GT, LT and EQ Flags will not change and will maintain the status produced by
the last instruction that was executed.
Instructions
25503 (ER)
25504 (CY)
25505 (GR)
25506 (EQ)
25507 (LE)
25402 (N)
Page
TIM
Unaffected
Unaffected
Unaffected
Unaffected
Unaffected
389
CNT
394
END(01)
OFF
OFF
OFF
OFF
OFF
OFF
381
STEP(08)
Unaffected
Unaffected
Unaffected
Unaffected
Unaffected
Unaffected
385
SNXT(09)
385
CNTR(12)
395
TIMH(15)
390
WSFT(16)
405
CMP(20)
Unaffected
Unaffected
432
MOV(21)
Unaffected
Unaffected
Unaffected
411
MVN(22)
412
BIN(23)
OFF
439
BCD(24)
Unaffected
440
ASL(25)
Unaffected
Unaffected
405
ASR(26)
OFF
406
ROL(27)
406
ROR(28)
407
COM(29)
Unaffected
Unaffected
Unaffected
479
ADD(30)
Unaffected
457
SUB(31)
458
Содержание SRM1 - PROGRAMING 02-2001
Страница 1: ...Programmable Controllers Cat No W353 E1 06 SYSMAC CPM1 CPM1A CPM2A CPM2C SRM1 V2 PROGRAMMING MANUAL ...
Страница 2: ...CPM1 CPM1A CPM2A CPM2C SRM1 V2 Programmable Controllers Programming Manual Revised February 2008 ...
Страница 3: ...iv ...
Страница 5: ...vi ...
Страница 9: ...x ...
Страница 15: ...xvi ...