Bit Counter - Bcnt(67); Frame Checksum - Fcs(- -) - Omron CQM1H - PROGRAM Programming Manual

Special Instructions
5-28-5 BIT COUNTER – BCNT(67)
Limitations
Description
Flags
5-28-6 FRAME CHECKSUM – FCS(– –)
Limitations
Description
Indirectly addressed EM/DM word is non-existent.
(Content of *EM/*DM word is not BCD, or the EM/DM area boundary
has been exceeded.)
A subroutine has called itself.
An active subroutine has been called.
Ladder Symbols
BCNT(67) @BCNT(67)
N
SB
R
N cannot be 0.
DM 6144 to DM 6655 cannot be used for R.
When the execution condition is OFF, BCNT(67) is not executed. When the
execution condition is ON, BCNT(67) counts the total number of bits that are
ON in all words between SB and SB+(N–1) and places the result in R.
ER: N is not BCD, or N is 0; SB and SB+(N–1) are not in the same area.
The resulting count value exceeds 9999.
Indirectly addressed EM/DM word is non-existent.
(Content of *EM/*DM word is not BCD, or the EM/DM area boundary
has been exceeded.)
EQ: ON when the result is 0.
Ladder Symbols
FCS(−−)
C
R
1
D
The 3 rightmost digits of C must be BCD between 001 and 999.
DM 6143 to DM 6655 cannot be used for D.
FCS(––) can be used to check for errors when transferring data through com-
munications ports.
When the execution condition is OFF, FCS(––) is not executed. When the exe-
cution condition is ON, FCS(––) calculates the frame checksum of the speci-
fied range by exclusively ORing either the contents of words R
IR, SR, AR, DM, EM, HR, TIM/CNT, LR, #
N
SB
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
R
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
@FCS(−−)
IR, SR, AR, DM, EM, HR, LR, #
C
R
1
IR, SR, AR, DM, EM, HR, TIM/CNT, LR
D
IR, SR, AR, DM, EM, HR, LR
Section 5-28
Operand Data Areas
N: Number of words (BCD)
SB: Source beginning word
R: Destination word
Operand Data Areas
C: Control data
R : First word in range
1
D: First destination word
to R
1
+N–1 or
1
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