Select unit, Table 7, Symbols used in form checksum equations – Vaisala MMT162 User Manual
Page 34
User's Guide ______________________________________________________________________
32 __________________________________________________________________ M210934EN-C
Checksums are calculated as described in the equations below.
1 =
∑
=
=
n
i
i
b
cs
1
2
256
mod
2 =
65536
mod
1
4
∑
=
=
n
i
i
b
cs
3 =
2
4
6
3
0
'
2
4
6
3
'
'
'
'
i
2
1
=
=
=
≠
≠
=
⊕
⊕
⊕
=
i
i
i
i
i
i
n
x
b
or
b
if
b
b
and
b
if
b
b
b
b
b
cs
Table 7
Symbols Used in FORM Checksum Equations
Symbol
Description
cs
2
Value of CS2 checksum in the output message.
cs
4
Value of CS4 checksum in the output message.
cs
x
Value of CSX checksum in the output message.
b
i
Value of the byte at position i (1-based) in the output message.
n
Number of bytes in the output message before the CS2, CS4,
or CSX field (including earlier checksum fields, if any).
⊕
Bit-wise exclusive-or operator.
36
Byte value of ASCII
$ character.
42
Byte value of ASCII
* character.
Select Unit
Use the UNIT command to select metric or non-metric output units.
UNIT [x]
where
x = M or N
where
M = Metric units
N = Non-metric units