# :DIFF Subsystem

:DIFF Commands

- :DIFF Subsystem
- :DIFF General Commands
- :DIFF Threshold Commands
- :DIFF CRECovery Commands
- :DIFF EYE Commands
- :DIFF Scaling and Units Commands
- :DIFF SNDR Setup Commands

The DIFF subsystem commands control differential electrical waveforms. In the `:DIFF` command syntax, differential waveforms are identified by the associated instrument connection number (from 1 to 8) and channel number (from 1 to 8). For example, this command sets the color of the differential waveform of an 86112A instrument installed at connections 3 and 4. Notice connection 3 channel 1 number 3_1 highlighted in red.

    :DIFF3_1:COLor TCOLor8

Traditional instruments take up two connections, either connections 1 and 2 or connections 3 and 4. For these type of instruments, the differential waveform is identified using the number for the left-most occupied connection. For example, `:DIFF1_1` or `:DIFF3_1`, respectively.

Single-connection instruments could have two channels. In this case, the differential waveform of an instrument installed at connection 4 would be identified as `:DIFF4_1`. Also, when Infiniium 2026 is configured with a simulated instrument, one-connection simulated instruments are available that have two channels. The following table show several examples of differential waveform identification.

Examples of Differential Waveform Numbers
Instrument Type | Installed Connections | Source Channels for Differential Waveform | Differential Channel Waveform Identification
--- | --- | --- | ---
Traditional Two-Connection, Dual Channel (for example, 86112A) | 1 & 2 | 1_1 and 2_1 | `:DIFF1_1`
3 & 4 | 3_1 and 4_1 | `:DIFF3_1`
Simulated or Future Single-Connection, Dual Channel | 1 | 1_1 and 1_2 | `:DIFF1_1`
2 | 2_1 and 2_2 | `:DIFF2_1`
3 | 3_1 and 3_2 | `:DIFF3_1`
4 | 4_1 and 4_2 | `:DIFF4_1`

## Example Command Sequence

    :DIFF3:DMODe ON
    :CHANnel1:FILTer:BANDwidth 20E+09
    :CHANnel2:FILTer:BANDwidth 20E+09
    *OPC?
    …
                      //  Your code to synchronize execution timing.
    :DIFF3:DISPlay ON