Command Notes (Scpi Commands - Data Format) - Keithley 2302 Instruction Manual

Command notes (SCPI commands — data format)
FORMat[:DATA] <type>
Parameters
This command is used to select the data format for transferring readings over the bus. The
reading(s) that is sent depends on the presently selected function (voltage, current, pulse-current,
DVM or long integration). See the :FUNCtion command (SENSe subsystem in
"Signal Oriented Measurement Commands"
NOTE
ASCII format
The ASCII data format is in a direct readable form for the operator. Most Basic languages
easily convert ASCII mantissa and exponent to other formats. However, some speed is
compromised to accommodate the conversion. The following shows the ASCII format for a
reading of 10.058 volts.
+1.00580000 E+01
IEEE754 formats
SREal will select the binary IEEE-754 single precision data format.
normal byte order format for each data element (voltage, current, etc.). 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. Not shown in
end of each data string.
Figure 11-1
IEEE-754 single precision data format
Test Equipment Depot - 800.517.8431 - 99 Washington Street Melrose, MA 02176
TestEquipmentDepot.com
<type> = ASCii
Regardless of which data format for output strings is selected, the power supply will
only respond to input commands using the ASCII format.
Figure 11-1
Header
# 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.
DISPlay, FORMat, and SYSTem
Select data format
ASCII format
SREal IEEE754 single precision format
DREal IEEE754 double precision format
(Section 10) for more information.
is a byte for the terminator that is attached to the
Byte 1 Byte 2
0 7 0
e
Section 2) and
Figure 11-1 shows the
Byte 3 Byte 4
7 0 7
f
11-5
0