User waveforms, constellations, and
fi
lters
Big-endian byte order
In many cases, 16-bit or 32-bit numbers must be encoded in a binary transmission.
The native encoding for numbers in computers follows one of two common
formats: little-endian and big-endian. The generators expect data in a big-endian
format. Most Intel based computers natively store numbers in a little-endian
format. For these machines, all binary numbers will have to be converted into a
big-endian format before being transmitted.
As an example, the decimal number 43,891 is represented by the hexadecimal
value 0xABCD. Storage of this number within the memory of a computer,
however, depends on the native storage format. In the big-endian format the
number is stored as the bytes AB CD. In the little-endian format, however, the
number is stored as the bytes CD AB (the bytes are swapped). Numbers stored
in this format will need to be swapped back into big-endian format before being
transmitted over the remote interface.
SRAM versus
fl
ash storage
The generators include 2 MB of SRAM and
fl
ash for storage of arbitrary
waveforms, constellations, and
fi
lters. SRAM is volatile memory that is lost
when power is removed from the instrument. Flash is nonvolatile memory that
is retained even when power is cycled. User data is always downloaded into
SRAM
fi
rst. Once downloaded, you can optionally copy the data into
fl
ash if
desired with one of the commands SAVW, SAVC, or SAVF. Waveforms may be
played directly out of SRAM or
fl
ash.
Using the
fi
le Assistant utility software
The TSG File Assistant is a utility software application that runs on Windows 7
and that allows you to convert custom user data
fi
les (waveforms, constellations,
and
fi
lters) from *.txt or *.csv
fi
les to
fi
les types supported by the generator (*.tsw,
*.tsc, or *.tsf). This utility also allows you to download supported
fi
le types to the
generator when it is connected to the Ethernet through a LAN connection.
NOTE.
Raw Socket Interface is not currently supported in the March 31, 2015
software version.
Download TSG File
Assistant
The TSG File Assistant utility software is available for download at
www.tek.com/downloads. To download the software, do the following:
1.
Go to www.tektronix.com/downloads.
2.
Select Software.
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TSG4100A Series RF Signal Generators User Manual
