Release notes for the Spike SCPI command set.

- Spike Version 4.0.4
* Added :SYSTem:OVERflow? command.

- Spike Version 4.0.0
* Support for VCO Characterization measurements.
* Support for Phase Noise Cross-Correlation measurements.

- Spike Version 3.9.6
* Added support for DDEMOD wide carrier estimation.

- Spike Version 3.9.0
* Added support for 8/16 FSK

- Spike Version 3.8.9
* FETCh:DDEMod? can now return constellation plot/traces for both PSK/QAM and FSK type signals.

- Spike Version 3.8.4
* Support for Noise Figure measurements.

- Spike Version 3.8.0
* FETCH:ZS? now returns average power.
* Added commands to retrieve spectrum plot in digital demod mode.
  - See DDEMOD:TRACE:SWEEP commands.
* Added commands to retrieve GPS position of LTE measurements in LTE mode.
* Added commands to configure LTE correlation threshold.
* Added commands to control and configure the audio player.

- Spike Version 3.5.22
* Support for new limit line functionality
* Added commands to hide the Spike application
  - DISPlay:HIDE <bool>
  - DISPlay:HIDE?

- Spike Version 3.5.21
* Support for LTE measurements.
* Added SCPI log utility.

- Spike Version 3.5.17
* Support for BLE measurements.
* Added command to retrieve current average trace count in sweep mode.
  - TRACe:AVERage:CURRent?
* Added commands for configuring maximum peak count in peak table.
  - [:SENSe]:PEAK:TABLE:MAX
  - [:SENSe]:PEAK:TABLE:MAX?

- Spike Version 3.5.15
* Added command to retrieve connection string for currently active device.
  - SYSTem:DEVice:CURRent?
  - Useful for reconnects

- Spike Version 3.5.14
* Added commands for new marker functions
  - CALCulate:MARKer:MAXimum:NEXT
  - CALCulate:MARKer:MINimum
* Added commands for new marker types
  - CALCulate:MARKer:MODE POSition|NOISE|CHPower|NDB
  - CALCulate:MARKer:CHPower:WIDth <freq>
  - CALCulate:MARKer:CHPower:WIDth?
  - CALCulate:MARKer:NDB[:OFFset] <double>
  - CALCulate:MARKer:NDB[:OFFset]?
  - CALCulate:MARKer:NDB:BANDwidth?
  - CALCulate:MARKer:NDB:RLEFt?
  - CALCulate:MARKer:NDB:RRIGht?
* Added a third reference oscillator state for output
  - SENSe:ROSCillator:SOURce INTernal|EXTernal|OUTput

- Spike Version 3.5.12
* Added ability to list and connect SM200C devices with the SYSTEM:DEVICE SCPI functions.

- Spike Version 3.5.7
* Added MIN and MAX options to sweep detector command.
  - [:SENSe]:SWEep:DETector:UNITs[?]
* Added trace copy command.
  - TRACe:COPY <int>
* Added trace math commands.
  - CALCulate:MATH[:STATe][?] <bool>
  - CALCulate:MATH:FIRST[?] <int>
  - CALCulate:MATH:SECond[?] <int>
  - CALCulate:MATH:RESult[?] <int>
  - CALCulate:MATH:OP[?]
  - CALCulate:MATH:OFFSet[?] <double>
* Added display line commands.
  - TRACe:DLINe[:STATe][?] <bool>
  - TRACe:DLINe:LEVel[?] <ampl>

- Spike Version 3.5.6
* Added SCPI compatibility for Zero-Span measurement mode.
  - Includes IQ data fetch.

- Spike Version 3.5.0
* Added SCPI commands for saving and loading user presets from a file.
  - SYSTem:PRESet[:USER]:SAVE
  - SYSTem:PRESet[:USER]:LOAD

- Spike Version 3.4.2
* Support for DDemod sync search.
* Support for DDemod equalization.
* Removed DDemod pattern trigger type.
* :TRIGger:DDEMod:IF:DELay command changed to :TRIGger:DDEMod:DELay
* Removed the following channel power commands:
  - :SENSe:CHPower:SPACing[?]
  - :SENSe:CHPower:COUNt[?]
  - :SENSe:CHPower:CENTer? <int>
  - :SENSe:CHPower:CHPower? <int>
  - :SENSe:CHPower:ACPower? <int>
* Added the following channel power commands:
  - :SENSe:CHPower:CHANnel:STATe[?] <int>
  - :SENSe:CHPower:CHANnel:OFFSet[?] <int>
  - :SENSe:CHPower:CHANnel:WIDth[?] <int>
  - :SENSe:CHPower:CHPower?
  - :SENSe:CHPower:CHPower:LOWer? <int>
  - :SENSe:CHPower:CHPower:UPPer? <int>
  - :SENSe:CHPower:ACPower:LOWer? <int>
  - :SENSe:CHPower:ACPower:UPPer? <int>

- Spike Version 3.3.3
* Support for WLAN measurements.

- Spike Version 3.3.2
* Added SCPI commands
  - SENSe:ROSCillator:SOURce for device timebase control
  - SYSTem:COMMunicate:GTLocal for putting Spike in local mode
  - SENSe:POWer:RF:RLEVel:UNIT? for checking amplitude units of ref level in Sweep mode
* Bug fix for :SYSTem:VERsion?

- Spike Version 3.3.1
* Support for spectrum emission mask (SEM) measurements.

- Spike Version 3.2.9
* Support for Path Loss Tables.
* Bug fixes
  - Capitalization should now be respected for string arguments (titles/names).

- Spike Version 3.2.5
* Support for Digital Demodulation custom constellations.

- Spike Version 3.2.4
* Support for Scalar Network Analysis measurements.
* Support for limit lines.
* Bug fixes
  - SYSTEM:IMAGE:SAVE command is now implemented.

- Spike Version 3.2.3
* Support for digital demodulation measurements.

- Spike Version 3.2.2
* Bug fixes
  - Fixed crashes on the following SCPI commands
    TRACE:XSTART?
    TRACE:XINCREMENT?
    TRACE:POINTS?
  - Fixed SENSE:POWER:RF:RLEVEL[?], short form did not match manual.
  - Fixed SENSE:SWEEP:TIME. Command was non-responsive.
* Updated examples to use the comma operator for querying comma separated lists.

- Spike Version 3.2.1
* Support for phase noise measurements. (SM200 and SA44/124 devices only)
* Support for harmonic measurements.

- Spike Version 3.2.0
* Initial release
* Support for sweep mode configuration, traces and markers.
* Support for channel power.
* Support for occupied bandwidth.