Mitsubishi Electronics MELSEC-F Manuel D’Utilisation
B-45
5 Buffer Memory (BFM)
5.4 Buffer Memory Details
A
Comm
on I
te
te
ms
B
FX
3U
-4AD
FX
3UC
-4
A
D
C
FX
3U
-4A
D
D
-A
D
P
D
FX
3G
-2A
D
D
-BD
E
FX
3U
-4DA
F
FX
3U
-4D
A
A
-AD
P
P
G
FX
3G
-1D
A
A
-BD
H
FX
3U
-3
A-
ADP
I
FX
3U
-4
A
D
-P
T
-
A
D
P
J
FX
3U
-4A
D
D
-P
TW
-
A
A
D
P
FX
3G
/FX
3U
/FX
3UC
PLC User's Manual - Analog Control Edition
FX
3U
-4AD/FX
3UC
-4AD (4-channel Analog Input)
5.4.23 BFM #127: Abrupt change detection status data automatic transfer-to data register
specification
Setting range: 0 to 7999
Initial value (at delivery) : K209
Numeric data type: Decimal (K)
Use this function to automatically transfer the abrupt change detection status data (BFM #27) to the data
register specified in BFM #127.
When abrupt change is detected, data will be automatically transferred from the 4AD to the PLC. For this
reason, the PLC does not need any program for reading the data, and the scan time of the PLC can be
shortened.
register specified in BFM #127.
When abrupt change is detected, data will be automatically transferred from the 4AD to the PLC. For this
reason, the PLC does not need any program for reading the data, and the scan time of the PLC can be
shortened.
→ For a detailed description of the abrupt change detection status data (BFM #27),
refer to Subsection 5.4.10.
2. Caution regarding abrupt change detection status data automatic transfer to data register
specification
• If a data register is already specified for the other automatic transfer functions, do not specify the same
data register.
• Be sure to turn on the abrupt change detection status data automatic transfer function (b6 of BFM #22) and
the abrupt change detection function (b2 of BFM #22).
• The data written to BFM #127 will be retained in the EEPROM.
3. Caution regarding EEPROM writing
If data is written to BFM #0, #19, #21, #22, #125 to #129, or #198, the data will also be written to the 4AD
EEPROM.
EEPROM.
→ For a detailed description of caution regarding EEPROM writing, refer to Subsection 5.4.1.
1. If "BFM #127 = K209 (initial value)"
Specified data register
Description
D209
Abrupt change detection status data in BFM #27