Data AcQuisition And Real-Time AnalysisScope - Spectrum - Spectrogram - Signal Generator
Software for Windows
Science with your Sound Card!
Contact us about
Multi-Channel Left and Right Streams
In Multi-Channel Outputs mode, each selected output channel must also have one or more output streams selected. These are chosen by means of an array of 64 buttons - 8 per channel, for all 8 channels.
The buttons are shown as Left Streams and Right Streams, with each having buttons labeled 0-3 to match the stream designations used in the Left and Right Wave Controls. Nevertheless, any of the 8 streams or any combination of streams can be used with any selected channel, and the same stream can be used by multiple channels.
Note, however, that the selected streams will be summed together to get the overall output for the selected channel. As for normal stereo mode, the instantaneous total must never be greater than 100%. If it does, the waveform peaks will be clipped at 100%, and the Generator Clip Indicator will be activated.
But while stereo mode only allows up to 4 streams to be summed, here you can sum up to 8. So if, for instance, you want to sum 8 equal-amplitude sine waves, the Level of each can be no greater than 12.5%. (You can, however, use 100% on each stream with carefully constructed tone burst sequences that never overlap.)
Note that unlike stereo mode, Multi-Channel Outputs mode allows streams that are modulation sources to be selected as outputs. This can be convenient for triggering external devices to sync with the modulation of an output signal, instead of the raw signal itself.
Macros for selecting the streams for each channel use the basic channel select names (FrontL, FrontR, Center, LowFreq, BackL, BackR, SideL, and SideR), but with additional prefixes and/or parameters.
Using the Center channel as an example, you can set a specific stream state using prefixes L.0. through L.3. or R.0. through R.3. with the #S parameter, as in L.2.Center#S=1 to set Left Stream 2 on for the Center channel. L.2.Center#S=0 sets it off and L.2.Center#S=x toggles the current state.
Alternatively, you can use Channel Select variable Ch to specify the channel and stream via Ch.Center#S=1, where Ch has previously been set to 0-3 (for L.0. to L.3.) or 4-7 (for R.0. to R.3).
Note that attempting to set the state of a disabled button will result in the macro aborting with a "Control disabled" message.
You can read the state of any stream button for a channel via a ?S query parameter, as in L.2.UX=Center?S to set variable UX to 1 if the L.2. stream is on, else 0. Note the curious use of prefixes here; prefixes must always appear on the left side of the macro statement, even though in this case they refer to the Center channel on the right side.
Alternatively, you can set all 8 stream states for a channel simultaneously using Center#N=X, where X is a bit-mapped value such that L.0. uses bit 0, and R.3. uses bit 7. The bit weights are thus:
L.0. (bit 0) = b00000001 = h01 = 1 L.1. (bit 1) = b00000010 = h02 = 2 L.2. (bit 2) = b00000100 = h04 = 4 L.3. (bit 3) = b00001000 = h08 = 8 R.0. (bit 4) = b00010000 = h10 = 16 R.1. (bit 5) = b00100000 = h20 = 32 R.2. (bit 6) = b01000000 = h40 = 64 R.3. (bit 7) = b10000000 = h80 = 128
A value of 0 sets all stream states off.
So, for example, to set L.1. and R.1. on and all others off, the value would be 2 + 32 = 34. You can enter binary values directly by starting the binary value with a 'b', as in Center#N=b00100010. Note that the bit order is opposite from the button order, where L.0. is on the left but is the least-significant bit. You can thus enter the bits of the binary number from right to left to get the proper value. Leading zeros are properly ignored, so Center#N=b100010 is equivalent to Center#N=b00100010.
Note that as with the #S individual stream select, attempting to toggle a disabled button on will result in the macro aborting.
You can read the states of all stream buttons for a channel via X=Center?N, where variable X is encoded using the same bit map as above.
Questions? Comments? Contact us!We respond to ALL inquiries, typically within 24 hrs.
Over 35 Years of Innovative Instrumentation
© Copyright 2007 - 2021 by Interstellar Research
All rights reserved