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 conver-
sion 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 equiva-
lent 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
SCPI Command Reference 5-29
Figure 5-2
IEEE754 single
precision data
format (32 data
bits)
Figure 5-3
IEEE754 double
precision data
format (64 data
bits)