Getnbits() – Teledyne LeCroy BPT - References Manual User Manual
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CATC S
CRIPTING
L
ANGUAGE
1.1
C
HAPTER
10
Reference Manual
Primitives
•
A space will insert a space before a positive signed integer. This only works with the
conversion characters
d
and
i
. If both a space and a plus sign are used, the space flag
will be ignored.
•
A hash mark (
#
) will prepend a
0
to an octal number when used with the conversion
character
o
. If
#
is used with
x
or
X
, it will prepend
0x
or
0X
to a hexadecimal
number.
•
A zero (
0
) will pad the field with zeros instead of with spaces.
•
Field width specification is a positive integer that defines the field width, in spaces, of the
converted argument. If the number of characters in the argument is smaller than the field
width, then the field is padded with spaces. If the argument has more characters than the
field width has spaces, then the field will expand to accommodate the argument.
GetNBits()
GetNBits (
Return value
None.
Comments
Reads
bit_count
bits from
bit_source
starting at
bit_offset
. Will
return null if
bit_offset
+
bit_count
exceeds the number of bits in
bit_source
. If
bit_count
is 32 or less, the result will be returned as an
integer. Otherwise, the result will be returned in a list format that is the same as the
input format.
GetNBits
also sets up the bit data source and global bit offset used
by
NextNBits
and
PeekNBits
. Note that bits are indexed starting at bit 0.
Example
raw = 'F0F0';
# 1111000011110000 binary
result = GetNBits ( raw, 2, 4 );
Trace ( "result = ", result );
The output would be
Parameter
Meaning
Default Value Comments
bit_source list, raw, or
integer
Can be an integer value (4 bytes) or a list of inte-
gers that are interpreted as bytes.
bit_offset integer
Index of bit to
start reading
from
bit_count integer
Number of
bits to read