Mitsubishi Electric GT1685 Connection Manual page 97

(4) Setting of the mask type (MELSEC-FX)
Set the item for monitoring or writing only the specified
bits of the buffer memory.
HINT HINT HINT
Mask type
The mask type is effective when using for the buffer
memories divided per 4 bits, such as an analog input
block.
(a) Mask type 0
Monitor and write the buffer memory value directly.
(b) Mask type 1
• (For 16 bits)
Monitor and write only b0 to b3 of the buffer
memory.
Example:
The monitor value is 0001
BM=4321 as mask type 1.
H
BM0 4 3
Monitor value 0 0
BM0=0001 when writing input value 4321
H
BM0=0000 as mask type 1.
H
Input value 4 3
BM0
0 0
(Before writing)
BM0
0 0
(After writing)
• (For 32 bits)
Monitor and write only b0 to b3 and b16 to 19 of
the buffer memory.
Example:
The monitor value is 00050001
BM0=87654321 as mask type 1.
H
BM0 8 7
Monitor value 0 0
BM0=00050001 when writing input value
H
87654321 to BM0=00000000
H
Input value
8 7
BM0
0 0
(Before writing)
BM0
0 0
(After writing)
when monitoring
H
2 1
H
0 1
H
to
H
2 1
H
0 0
H
0 1
H
when monitoring
H
6 5 4 3 2 1
H
0 5 0 0 0 1
H
as mask type 1.
H
6 5 4 3 2 1
H
0 0 0 0 0 0
H
0 5 0 0 0 1
H
(c) Mask type 2
• (For 16 bits)
Monitor and write only b4 to b7 of the buffer
memory.
Example:
The monitor value is 0002
BM0=4321 as mask type 2.
H
BM0 4 3
Monitor value 0 0
BM0=0010 when writing input value 4321
H
BM0=0000 as mask type 2.
H
4 3 2
Input value
BM0
0 0 0
(Before writing)
BM0
0 0 1
(After writing)
• (For 32 bits)
Monitor and write only b4 to b7 and b20 to 23 of
the buffer memory.
Example:
The monitor value is 00060002
BM0=87654321 as mask type 2.
H
BM0 8 7
Monitor value 0 0
BM0=00500010 when writing input value
H
87654321 to BM0=00000000
H
Input value 8 7 6
BM0
0 0 0
(Before writing)
BM0
0 0 5
(After writing)
(d) Mask type 3
• (For 16 bits)
Monitor and write only b8 to b11 of the buffer
memory.
Example:
The monitor value is 0003
BM0=4321 as mask type 3.
H
BM0 4 3
Monitor value 0 0
BM0=0100 when writing input value 4321
H
BM0=0000 as mask type 3.
H
Input value 4 3 2
BM0
0 0 0
(Before writing)
BM0
0 1 0
(After writing)
2. DEVICE RANGE THAT CAN BE SET
when monitoring
H
2 1
H
0 2
H
to
H
1
H
0
H
0
H
when monitoring
H
6 5 4 3 2 1
H
0 6 0 0 0 2
H
as mask type 2.
H
5 4 3 2 1
H
0 0 0 0 0
H
0 0 0 1 0
H
when monitoring
H
2 1
H
0 3
H
to
H
1
H
0
H
0
H
2 - 5
1
2
3
4
5
6
7
8