Mitsubishi Electronics MELSEC-F Manuel D’Utilisation
B-46
5 Buffer Memory (BFM)
5.4 Buffer Memory Details
FX
3G
/FX
3U
/FX
3UC
PLC User's Manual - Analog Control Edition
FX
3U
-4AD/FX
3UC
-4AD (4-channel Analog Input)
5.4.24 BFM #128: Over-scale status data automatic transfer-to data register specification
Setting range: 0 to 7999
Initial value (at delivery) : K210
Numeric data type: Decimal (K)
Use this function to automatically transfer the over-scale status data (BFM #28) to the data register specified
in BFM #128.
When over-scale 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.
in BFM #128.
When over-scale 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 over-scale status data (BFM #28), refer to Subsection 5.4.11.
2. Cautions regarding over-scale 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 over-scale status data automatic transfer function (b7 of BFM #22).
• The data written to BFM #128 will be retained in the EEPROM.
• The data written to BFM #128 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.
5.4.25 BFM #129: Error status data automatic transfer-to data register specification
Setting range: 0 to 7999
Initial value (at delivery) : K211
Numeric data type: Decimal (K)
Use this function to automatically transfer the error status data (BFM #29) to the data register specified in
BFM #129.
When an error 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.
BFM #129.
When an error 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 error status data (BFM #29), refer to Subsection 5.4.12.
2. Cautions regarding error 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 error status data automatic transfer function (b8 of BFM #22).
• The data written to BFM #129 will be retained in the EEPROM.
• The data written to BFM #129 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 #128 = K210 (initial value)"
Specified data register
Description
D210
Over-scale status data in BFM #28
1. If "BFM #129 = K211 (initial value)"
Specified data register
Description
D211
Error status data in BFM #29