Omron CVM1D, Operation Manual

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139
Each time the instruction is executed, the PV (content of D
2
) is compared to the
eight SVs in S through S+7, and if any of the SVs is less than or equal to the PV,
the corresponding Completion Flag (D
1
bits 00 through 07) is turned ON. For
greater accuracy, the same MTIM(122) instruction can be input into the program
several times so the PV:SV comparison is made more frequently.
The timer can be reset by turning ON the reset bit (bit 08 of D
1
), which resets the
PV and all Completion Flags to zero. Counting resumes from zero when the re-
set bit is turned OFF if the instruction execution condition is ON.
The pause bit (bit 09 of D
1
) can be turned ON to stop counting while maintaining
the status of the PV and Completion Flags. The MTIM(122) instruction is treated
as a NOP(000) instruction when the pause bit is ON and the reset bit is OFF.
When the pause bit is turned OFF, counting resumes from the previous PV.
If D
1
is in the CIO, G, or A Area, the reset bit and pause bit can be controlled with
SET(016) and RSET(017). If D
1
is in the DM or EM Area, these bits can be con-
trolled with the ANDW(130) and ORW(131) instructions. The pause bit and the
reset bit are effective only when the instruction execution condition is ON.
When fewer than eight outputs are needed, set the SV that follows the last one to
0000. SVs following the one set to 0000 are not compared to the PV.
The following figure shows the functions of bits in D
1
.
15 to 10 not used 09 08 07 06 05 04 03 02 01 00
Completion Flags for
SVs in S through S+7
(Bit 0n contains the
Flag for the SV in
S+n.)
Pause Bit
Reset Bit
D
1
:
Operation of MTIM(122) is the same in CVM1D and C/CVM1/CV-series PCs ex-
cept for the timer precision and PV refreshing in jumped program sections.
1, 2, 3... 1. Timer Precision
MTIM(122) instruction errors can be one cycle time or more (up to two cycle
times). The error range is
±
(100 ms + cycle time).
2. Operation of the MTIM(122) Instruction between JMP(004) and JME(005)
•
The timer PV is refreshed every cycle during program execution.
•
The timer operates normally while the execution condition of JMP(004) is
ON.
•
The timer does not operate while the timer is jumped (while the execution
condition of JMP(004) is OFF), whether the timer’s execution condition is
ON or OFF.
Precautions S cannot be one of the last seven addresses in a data area because this operand
designates the first of eight words.
The set value must be BCD between 000.0 and 999.9. The decimal point is not
entered.
Caution A50003 (Error Flag) will not turn ON and execution will continue even if the SV is
not BCD.
The MTIM(122) PV is inaccurate when the time between instruction executions
exceeds 1.6 s. The same MTIM(122) instruction can be input into the program
several times so the instruction is executed more frequently, but only as many as
necessary should be added to minimize the program execution time.
The set values in S through S+7 must be BCD, but the ER (A50003) Flag will not
be turned ON, and the instruction will be executed even if the contents are not
BCD.
Differences in CVM1D and
C/CVM1/CV-series PCs
Timer and Counter Instructions
Section 5-13