MagnaDC xGen Migration Guide: SCPI Command Compatibility

Magna-Power introduced its MagnaDC xGen products, which brings significant enhancements in control technology by transitioning from analog control managed by a microprocessor in previous generation (GEN1) to fully digital control using multiple DSPs. While the SCPI command sets remain largely consistent, there are notable differences to be aware of for a smooth transition.

This knowledge base article provides the differences between GEN1 SCPI commands to successfully transition existing software to supported xGen SCPI commands. Many new commands were also introduced in the xGen platform, providing advanced functionality that is not available on GEN1 products; these new commands are not described in this article.

Definitions

• MagnaDC GEN1: SL Series, XR Series, TS Series, MS Series, MT Series, and ML Series (and legacy PQA/PQD Series)
• MagnaDC xGen: SLx Series
• <NR1>: Digits with an implied decimal point assumed at the right of the least-significant digit. Example: 273
• <NR2>: Digits with an explicit decimal point. Example: .0273
• <NR3>: Digits with an explicit decimal point and an exponent. Example: 2.73E+2

Key Similarities

• Command Structure: Both series utilize ASCII textual SCPI commands terminated by a new line (<NL>) or carriage return-new line (<CR><NL>).
• Data Types: Both support <NR1>, <NR2>, and <NR3> formats.
• Subsystem Organization: Commands are categorized similarly into subsystems (MEASure, OUTPut, SOURce, CONFigure, STATus, SYSTem).

Notable Differences

CONFigure Subsystem

• Control Mode
  • MagnaDC GEN1: Uses separate commands for internal/external control (CONTrol:INTernal, CONTrol:EXTernal) to enable and disable various control interfaces.
  • MagnaDC xGen: A new lock (CONFigure:LOCK) command to lock out the front panel when entry from the front panel is not desired.
• Set Point Source
  • MagnaDC GEN1: Command CONFigure:SETPT allows selecting rotary, keypad, external programming, or remote.
  • MagnaDC xGen: Command CONFigure:SOURce allows choosing between local, function generator, or external analog input.

OUTPut Subsystem

• Auto-sequencing (ARM)
  • MagnaDC GEN1: Uses OUTPut:ARM command to manage auto-sequencing memory steps on units with the D Version front panel.
  • MagnaDC xGen: Does not have auto-sequencing at this time and OUTPut:ARM is not available.

SOURce Subsystem

• Slew Rates
  • MagnaDC GEN1: Does not explicitly specify commands for slew rates.
  • MagnaDC xGen: Includes detailed slew rate commands for current, voltage, and power (CURRent:SLEW, VOLTage:SLEW, POWer:SLEW) for rising and falling transitions, enhancing precise control.
• Comprehensive Set-Point Command
  • MagnaDC GEN1: Individual commands (VOLTage, CURRent).
  • MagnaDC xGen: Unified command (SOURce:SETPoint) setting current, voltage, power, and resistance simultaneously.

MEASure Subsystem

• Measurement Queries
  • MagnaDC GEN1: Provides simple queries (MEASure:VOLTage?, MEASure:CURRent?).
  • MagnaDC xGen: Provides the same MEASure:VOLTage?, MEASure:CURRent? queries, but also offers expanded queries including power (MEASure:POWer?) and scalar measurements, returned with a single query (MEASure:SCALar:ALL[:DC]?).

STATus and SYSTem Subsystems

• Additional Fault and Status Queries
  • MagnaDC xGen: Changes to the register mappings for fault and system status reporting (STATus:QUEStionable:CONDition?, STATus:REGister?).
• Communication Protocols
  • MagnaDC xGen: Introduces a configurable communication protocol command (CONFigure:COMMunication:PROTocol) allowing switching between SCPI, MagnaLINK, Modbus, and industrial network protocols.

Recommended Migration Steps

1. Review SCPI Commands: Carefully compare commands your application currently uses from the MagnaDC GEN1 documentation against the MagnaDC xGen command reference.
2. Update Scripts and Software: Adjust scripts, especially if using auto-sequencing, slew rates, or set-point configurations.
3. Test in Stages: Initially test critical commands individually to ensure compatibility and to address any differences or additional configurations needed in the MagnaDC xGen.

By understanding these changes and systematically updating your scripts, you can smoothly transition existing software from the MagnaDC GEN1 to the advanced digital control of the MagnaDC xGen.