Mitsubishi Electric Q01UCPU User Manual page 539

(2)
Method of avoiding "OPERATION ERROR" (error code: 4140) in the floating-point data
comparison instructions
As shown in the modification examples below, connect the contacts of valid data flag in series for each floating-
point data comparison instruction. (Use AND connection for connecting the contact of the valid data flag and the
floating-point data comparison instruction.)
Make sure that there is no line (OR connection) between the valid data flag and the floating-point data
comparison instruction.
<Modification example 1>
(Before modification)
E<= D100
Valid
data
flag
D100
E>=
<Modification example 2>
(Before modification)
E<= D100
Valid
data
flag
M200 M201
(After modification)
E10
Valid
data
flag
E200
Valid
data
flag
Make sure that there is no line (OR connection)
between the signal which shows the
floating-point data validity (valid data flag) and
the floating-point data comparison instruction.
(After modification)
E10
Valid
data
flag
Valid
data
flag
E<= D100 E10
D100 E200
E>=
E<= D100 E10
M200 M201
APPENDICES
A
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