Figure 5-2 Ieee754 Single Precision Data Format (32 Data Bits); Figure 5-3 Ieee754 Double Precision Data Format (64 Data Bits) - Keithley 2010 User Manual

Figure 5-2
IEEE754 single
precision data format
(32 data bits)
Figure 5-3
IEEE754 double
precision data format
(64 data bits)
SREal will select the binary IEEE754 single precision data format.
Figure 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 entire data
string is preceded by a single 2-byte header that is the binary equivalent of an
ASCII # sign and 0.
Header Byte 1
# 0
7 0 7
s e
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.
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.
Header Byte 1
# 0
7 0 7
s e
Bytes 3, 4, 5, and 6 not shown. Bytes 3, 4, 5, and 6 not shown.
s = sign bit (0 = positive, 1 = negative) s = sign bit (0 = positive, 1 = negative)
e = exponent bits (11) e = exponent bits (11)
f = fraction bits (52) f = fraction bits (52)
Normal byte order shown. For swapped byte order, Normal byte order shown. For swapped byte order,
bytes sent in reverse order: Header, Byte 8, bytes sent in reverse order: Header, Byte 8,
Byte 7 .... Byte 1. Byte 7 .... Byte 1.
The Header is only sent once for each measurement conversion. The Header is only sent once for each measurement conversion.
SCPI Command Reference
Byte 2 Byte 3
0 7 0
f
entire reading string
Byte 2 Byte 7
0 7
f
entire reading string
Byte 4
7 0
Byte 8
0 7 0
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