Keithley 2700 - Page 358

Model 2700 Multimeter/Switch System User’s Manual FORMat and Misc SYSTem Commands 14-5
Figure 14-2
IEEE-754 data formats
Measure
Conversion #1
Measure
Conversion #2
Measure
Conversion #10
s
7 0707070
ef
Byte 1 Byte 2 Byte 3 Byte 4
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.
A. Single precision data format (32 data bits)
s
7 0707070
ef
Byte 1 Byte 2 Byte 7 Byte 8
Bytes 3, 4, 5, and 6 not shown.
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.
B. Double precision data format (64 data bits)
Data Element
Data Element
Header
#0
Bytes
1 - 4
Bytes
1 - 4
Bytes
1 - 4
Bytes
1 - 4
Bytes
1 - 4
Bytes
1 - 4
Bytes
1 - 4
Bytes
1 - 4
Bytes
1 - 4
Data
Element
(reading)
Data
Element
(timestamp)
Data
Element
(units)
Data
Element
(units)
Data
Element
(reading)
Data
Element
(timestamp)
Data
Element
(reading)
Data
Element
(timestamp)
Data
Element
(units)
C. Example data string showing #0 Header