Select unit, Table 7, Symbols used in form checksum equations – Vaisala MMT162 User Manual

Page 34

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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]<cr>

where
x = M or N

where
M = Metric units

N = Non-metric units

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