VXI VT1538A SENSeFREQuencyAPERture?, SENSeFREQuencyLIMitLOWer, Related Commands Sensfreqaper

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[SENSe:]FREQuency:APERture?

[SENSe:]FREQuency:APERture? <channel> returns the currently set APERture time.

Parameters


	Parameter	Parameter	Range of	Default
	Name	Type	Values	Units

	channel	string	100 - 163	none

Comments • If the channel specified is on an SCP that doesn’t support this function, an error will be generated. See your SCP’s User’s Manual for its capabilities.

•Related Commands: SENS:FREQ:APER

•Returned Value: returns numeric aperture in seconds, The type is float32.

•Send with VXIplug&play Function: hpe14XX_cmdReal64_Q(...)

SENSe:FREQuency:LIMit:LOWer

[SENSe:]FREQuency:LIMit:LOWer <freq_limit>,<ch_list> allows you to specify a frequency lower limit beyond which the E1538A will stop waiting for a signal transition and will return a frequency value of zero. Conceptually, this is an input signal period time-out.

Parameters


	Parameter	Parameter	Range of	Default
	Name	Type	Values	Units

	freq_limit	numeric (float32)	.01667 to 250	Hz

	ch_list	string	100 - 163	none

Comments • <ch_list> must be channels on an E1538A SCP.

Note Although SENS:FREQ:LIM:LOW can set a "timeout period" as long as 60 seconds (.01667Hz), the lowest frequency measurement supported by the E1538A is 1 Hertz.

•The period associated with the FREQ:LIMit:LOWer frequency is the time the SCP will allow for any single cycle period.

At any time during the frequency measurement, if the signal’s period

48 Agilent E1538A Enhanced Frequency/Totalize/PWM SCP

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Contents VT1538A VXI Technology, Inc Introduction Support Resources User’s and Scpi Programming Manual Page Agilent E1538A Enhanced Frequency/Totalize/PWM SCP About this ManualIntroduction Identifying the Plug-on Important Setting Configuration Switches Switch Location and Example SettingsInstallation Connecting To The Terminal ModuleRecommended Signal Connections E1419A Option 11 Terminal Module ConnectionsInput and Output Characteristics Recommended Connections and Voltage LimitsVRS Mode Input Operation SCP Channels 0 & 1 only E1538A Input/Output CharacteristicsProgramming With Scpi Commands Shows the VRS mode input characteristicsConfiguring I/O Direction Setting the Input Threshold LevelDetermining the Input Threshold Level Inppol NormReading Static Digital State To set channels 40 through 43 to input digital statesTotalize Positive or Negative Edge State Changes Init SENSDATACVT? @44About Period Frequency Measurements SENSDATACVT? @45 SENSDATACVT? @45 Agilent E1538A Enhanced Frequency/Totalize/PWM SCP Agilent E1538A Enhanced Frequency/Totalize/PWM SCP Sense Quadrature Position Sensfuncquad 0,@148,149RPS Example of Rotational Velocity Sense Sense Rotational VelocityControlling Output Polarity Output Static Digital StateVariable Width Pulse Per Trigger Variable Width Pulse Train PWM Variable Frequency Fixed Width Pulse Train FM Variable Frequency Square-Wave Pulse Train Rotationally Positioned Pulse Output Rotational Pulse Command Usage Algupdate Init Example of variable position, preset width RST Sensfuncrvel 12,MISS,@140Variable Position, Width Preset by Time Example of variable width by angle, preset position Example of variable width by time, preset position Fixed Position, Variable Width by AngleALGSCALAR’ALG1’,’Width2’,.010 Stepper Motor Control Use the command Stepping mode valuesSensfuncvolt @100 Full Step Mode, Full and Half Speed, 4-Channel Page RST and *TST important Scpi Command Reference Command Syntax For newer Units onlyCommand Syntax For newer Units only Discussed INPutPOLarity INPutPOLarity?Parameters CommentsINPutTHResholdLEVel Level can be set to a resolutionINPutTHResholdLEVel? OUTPutPOLarity? OUTPutPOLaritySend with VXIplug&play Function hpe14XXcmdReal64Q SENSeFREQuencyAPERture SENSeFREQuencyAPERture? Related Commands SensfreqaperSENSeFREQuencyLIMitLOWer Init SENSeFREQuencyLIMitLOWer? Related Commands INPutPOLaritySENSeFUNCtionCONDition SENSeFUNCtionFREQuency SENSeFUNCtionPERiodSENSeFUNCtionPWIDth SENSeFUNCtionQUADratureSENSeFUNCtionRVELocity RPS SENSeFUNCtionTOTalize SENSePERiodAPERture SENSePERiodAPERture? SENSePERiodLIMitUPPerInit SENSePERiodLIMitUPPer? SENSePERiodMODESENSePERiodMODE? Related Commands SENSePERiodMODESENSePERiodNPERiods SENSePERiodRANGeUPPer SENSePERiodNPERiods?Send with VXIplug&play Function hpe14XXcmdInt32Q SENSePERiodRANGeUPPer? SENSeTOTalizeRESetMODERST Condition is Send with VXIplug&play Function hpe14XXcmd SENSeTOTalizeRESetMODE? SOURceFMSTATeSOURceFMSTATe? Send with VXIplug&play Function hpe14XXcmdInt16QSOURceFUNCtionRPULse SOURceFUNCtionSHAPeCONDition SOURceFUNCtionSHAPePULSeSOURceFUNCtionSTEPper SOURceFUNCtionSHAPeSQUareComments Send with VXIplug&play Function hpe14XXcmd Relationship of minvel, and maxvel SOURcePULMSTATe Usage See Stepper Motor Control onSOURcePULMSTATe? SOURcePULSePERiodSOURcePULSePERiod? SOURcePULSeWIDThSOURceRPULsePOSitionANGLe SOURcePULSeWIDTh?33,554,430 to 33,554,430 SOURRPULseVARType SOURceRPULsePOSitionANGLe?Usage SOURRPULseVARType? SOURceRPULseWIDThANGLeSOURceRPULseWIDThTIME SOURceRPULseWIDThANGLe?00000787 to SOURceRPULseWIDThTIME? Specifications General SpecificationsFrequency Measurement Pulse Width Measure Rotational Pulse Source