Yokogawa Standalone MW100 - Manual (Page 17)

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Start Bit Pos.
You can specify a start bit position for extraction of data to be measured included in the data field.
Enter the lsb number of the measured data. See below for how to count bit numbers in the MX118.
The values that can be selected vary depending on the Value Type setting.
Signed: 0–62
Unsigned: 0–63
Float: 0–32
Double: 0 (fixed)
Bit Length
Specify the data to be measured in terms of the number of bits.
The values that can be selected vary depending on the Value Type and Start Bit Pos settings.
Signed: 2–64 (however, Bit Length ≤ (64–Start Bit Pos) )
Unsigned: 1–64 (however, Bit Length ≤ (64–Start Bit Pos) )
Float: 32 (fixed)
Double: 64 (fixed)
Endian
Select the byte order when receiving data from the data field of Big or Little.
Big: Big Endian
Little: Little Endian
Counting Bit Numbers
The method for counting bit numbers differs depending on the Endian setting.
For details, see appendix 4.3, "Example of Extracting Measured Data."
▪ For Big Endian
From the start of the data field, starting with msb of the MSB, bit numbers decrease in units of
bytes or bits from left to right.
In this case, the data field is considered to be 8 bytes, and for data fields less than 8 bytes, they
are counted from the top of the byte.
For Little Endian
From the start of the data field, starting with the msb of the LSB, bit numbers increase in units of
bits from right to left, and in units of bytes from left to right.
MSB： most sig. byte
LSB： least sig. byte
msb： most sig. bit
lsb： least sig. bit
LSB MSB
msb lsb
63 56 bit
63・・・・・・56 55・・・・ ・・・・ 8 7・・・・・・ 0 bit
7・・・・・・ 0 15・・・・ ・・・・ 48 63・・・・・・56 bit
MSB LSB
msb lsb
7 0 bit
MSB： most sig. byte
LSB： least sig. byte
msb： most sig. bit
lsb： least sig. bit