Keithley TEC SourceMeter 2510, User Manual

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10-20 SCPI Command Reference Models 2510 and 2510-AT User’s Manual
IEEE-754 single precision format
REAL,32, or SREal will select the binary IEEE-754 single precision
data format.
Figure 10-2 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 4-byte 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.
NOTE This model terminates the binary data string with LF + EOI. If your program is
set to terminate on CR and/or LF, data transfer may terminate prematurely
because one or more data bytes has a CR or LF value. To avoid the problem, set
your program to terminate on EOI only.
Figure 10-2
IEEE-754 single precision data format (32 data bits)
During binary transfers, never un-talk the Model 2510 until after the
data is read (input) to the computer. Also, to avoid erratic operation, the
readings of the data string (and terminator) should be acquired in one
piece. The header (#0) can be read separately before the rest of the
string.
The number of bytes to be transferred can be calculated as follows:
Bytes=2+(Rdgs
×
4) + 1
where 2 is the number of bytes for the header (#0).
Rdgs is the product of the number of selected data
elements, arm count, and trigger count.
4 is the number of bytes for each reading.
1 is the byte for the terminator.
s
# 0
7 0 7 0 7 0 7 0
e f
Header 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.
The header and terminator are sent only once for each READ?