Keithley 2001 Operator's Manual page 241

REAL,32 or SREal will select the binary IEEE754 single precision data format. cáÖìêÉ=QJOM= 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 will be 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.
REAL,64 or DREal will select the binary IEEE754 double precision data format and is shown in cáÖìêÉ
QJON= (normal byte order shown). This format is similar to the single precision format except that it is 64
bits long.
2001-900-01 Rev. K / August 2010
Header Byte 1
# 0
7
s
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.
cáÖìêÉ=QJOM
IEEE754 single precision data format (32 data bits)
Reading
±1.2345678E±00NVDC, ±1234567.123456secs, ±123456rdng#, 01intchan
Mantissa Exponent
Status:
N = Normal
O = Overflow
R = Reference (Rel)
cáÖìêÉ=QJNV
ASCII data format
Byte 2
0 7 0 7
e
Time Stamp
Units
(seconds)
Units:
VDC = DC Volts
VAC = AC Volts
ADC = DC Current
AAC = AC Current
OHM = 2-wire Resistance
OHM4W = 4-wire Resistance
HZ = Frequency
C = Temperature in °C
F = Temperature in °F
K = Temperature in K
IEEE-488 Reference
Byte 3 Byte 4
0 7
f
Reading Channel
Number Number
Units
(reading
Units:
number)
intchan = Internal channel
extchan = External channel
00 = No channel
01 to 80 = Channel Number
0
4-83