User manual

SREAL will select the binary IEEE754 single precision data format. Fig-
ure 5-2 shows the normal byte order format for each data element. For
example, if three valid elements are specified, the data string for each
reading conversion is made up of three 32-bit data blocks. Note that the
data string for each reading conversion is preceded by a 2-byte header
that is the binary equivalent of an ASCII # sign and 0.
DREAL selects the binary IEEE754 double precision data format and is
shown in Figure 5-3 (normal byte order shown). This format is similar to
the single precision format except that it is 64 bits long.
Byte 1
70
Header
# 0
Byte 2
70
Byte 3
70
Byte 4
70
se f
s = sign bit (0 = positive, 1 = negative)
e = exponent bits (8)
f = fraction bits (23)
Normal byte order shown. For swapped byte order,
bytes sent in reverse order: Header, Byte 4, Byte 3,
Byte 2, Byte 1.
The Header is only sent once for each measurement conversion.
Byte 1
70
Header Byte 2
70
Byte 7
70
Byte 8
70
se f
s = sign bit (0 = positive, 1 = negative)
e = exponent bits (11)
f = fraction bits (52)
Normal byte order shown. For swapped byte order,
bytes sent in reverse order: Header, Byte 8,
Byte 7 .... Byte 1.
The Header is only sent once for each measurement conversion.
Bytes 3, 4, 5, and 6 not shown.
# 0
Figure 5-2
IEEE754 single
precision data
format (32 data
bits)
Figure 5-3
IEEE754 double
precision data
format (64 data
bits)
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