B&K Precision 2552-2559 - Programming Manual - Manual (Page 135)

DSO: TEMPLATE
Explanation of the formats of waveforms and their descriptors on the
DSO
A descriptor and/or a waveform consists of one or several logical data blocks
whose formats are explained below.
Usually, complete waveforms are read: at the minimum they consist of
the basic descriptor block WAVEDESC
a data array block.
Some more complex waveforms, e.g. Extrema data or the results of a Fourier
transform, may contain several data array blocks.
When there are more blocks, they are in the following sequence:
the basic descriptor block WAVEDESC
auxiliary data array block
data array block
In the following explanation, every element of a block is described by a
single line in the form
: ;
where
= position in bytes (decimal offset) of the variable,
relative to the beginning of the block.
= name of the variable.
= string up to 16-character name
terminated with a null byte
byte 08-bit signed data value
word 16-bit signed data value
long 32-bit signed data value
float 32-bit IEEE floating point value
with the format shown below
31 30 .. 23 22 ... 0 bit position
s exponent fraction
where
s = sign of the fraction
exponent = 8 bit exponent e
fraction = 23 bit fraction f
and the final value is
(-1)**s * 2**(e-127) * 1.f
double 64-bit IEEE floating point value
with the format shown below
63 62 .. 52 51 ... 0 bit position
s exponent fraction
where
s = sign of the fraction
exponent = 11 bit exponent e
fraction = 52 bit fraction f
and the final value is
(-1)**s * 2**(e-1023) * 1.f
enum enumerated value in the range 0 to N
represented as a 16-bit data value.
The list of values follows immediately.
The integer is preceded by an _.
time_stamp double precision floating point number,
for the number of seconds and some bytes
for minutes, hours, days, months and year.
double seconds (0 to 59)
byte minutes (0 to 59)
byte hours (0 to 23)