Bfm#19: Data Change Disable; Bfm#20: Initialization Function (Resetting To Factory Default Status; Bfm#21: Input Characteristics Writing - Mitsubishi Electric MELSEC-FX3S Series Manual

FX /FX /FX /FX /FX
3S 3G 3GC 3U
FX -4AD/FX -4AD (4-channel Analog Input)
3U 3UC
5.4.5

BFM#19: Data change disable

Disables adjustment of the following BFMs:
• Input mode specification (BFM#0)
• Input characteristics writing (BFM#21)
• Offset data (BFM#41 to #44)
• Automatic transfer-to data register specification (BFM#125 to #129)
• Data history sampling time setting (BFM#198)
Set the value of BFM#19 (Data change disable) as follows:
Set value
K2080
Value other than K2080
1. 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.
→ For a detailed description of caution regarding EEPROM writing, refer to Subsection 5.4.1.
5.4.6

BFM#20: Initialization function (resetting to factory default status)

Use this function to initialize all data in BFM#0 to #6999, to the factory default status.
Set value
K0
K1
Set "K1" to initialize all data. When initialization is complete, "K0" will be set automatically.
1. Caution regarding initialization function setting
• It takes approximately 5 seconds to initialize all the data.
• Priority is given to BFM#19 which prevents a data from being changed. To initialize, set K2080 in BFM#19.
5.4.7

BFM#21: Input characteristics writing

Channel numbers are assigned to the 4 lower bits of BFM#21. If any of these bits are turned on, the offset
data (BFM#41 to #44) and gain data (BFM#51 to #54) of the corresponding channel will be written to the
internal memory (EEPROM). When written to the internal memory, the data will become valid.
1. BFM#21 bits channel number assignment
Bit No.
b0 Channel-1 offset data (BFM#41) and gain data (BFM#51) writing
b1 Channel-2 offset data (BFM#42) and gain data (BFM#52) writing
b2 Channel-3 offset data (BFM#43) and gain data (BFM#53) writing
b3 Channel-4 offset data (BFM#44) and gain data (BFM#54) writing
b4 to b15 Not used.
The WRITE command can be given to two or more channels at the same time. (Set "H000F" to write all
channel data to the EEPROM.) When writing is complete, "H0000" (b0 to b3: OFF) will be set automatically.
B-30
PLC User's Manual - Analog Control Edition
3UC
Description
Normal
Initializes all data
Setting range: K2080, or value other than K2080
• Initialization function (BFM#20)
• Convenient functions (BFM#22)
• Gain data (BFM#51 to #54)
Description
Data change enabled.
Data change disabled.
Description
5 Buffer Memory (BFM)
5.4 Buffer Memory Details
Initial value (at delivery): K2080
Numeric data type: Decimal (K)
Setting range: K0 or K1
Initial value: K0
Numeric data type: Decimal (K)
Initial value: H0000
Numeric data type: Hexadecimal (H)