Hi,
You didn't say what you are trying to do with the channel, but I'm guessing that you are trying to turn the channel on/off for the display. You've probably already figured out that the channel name is passed as a parameter for the channel configuration functions. I don't think IVI supports control of the channel display. However, you can send a text command to the TDS210 using VISA functions. The information you need can be found in the programmers manual, available for download at www.tektronix.com (look under Support). I've extracted the relevant information below.
Mark
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SELect:
Controls the display of waveforms. This command is equivalent to turning a waveform on or off from the oscilloscope front panel.
Syntax:
S
ELect: { OFF | ON }
OFF turns off the display of the specified waveform.
ON turns on the display of the specified waveform.
can be CH,MATH,or REF,y>
EXAMPLE: SELECT:CH2 ON
displays channel 2.