PCDK Read numeric register in C#

Unless I'm reading it wrong, I think it's because you are getting the register value using the "RegLong Property". Long data type is for integers only.

The Fanuc PCDK documentation has a description for the property stating this:

Quote

FRCRegNumeric.RegLong Property

Description:

Returns/sets the long value for the numeric register.

Syntax:

[lngRegInt = ] objNumReg.RegLong

Parts:

objNumReg as FRCRegNumeric lngRegInt as Long

Remarks:

This property will raise an error if it is read when the type is not INTEGER (Type property is not frIntegerType). When this property is set the register type is automatically converted to INTEGER (Type property is set to frIntegerType).

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To get the floating-point value of a numeric register, you will want to use the standard RegNumerics Property here:

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FRCRobot.RegNumerics Property

Description:

Returns the robot numeric registers.

Syntax:

[objNumRegs = ]objRobot.RegNumerics

Parts:

objRobot as FRCRobot objNumRegs as FRCVars

Remarks:

This property provides access to the numeric registers of the controller. These registers are typically accessed from TP programs.

See Also:

FRCRobot Object Overview FRCVars Object Overview FRCVar Object Overview FRCRegNumeric Object Overview

Code

Example of getting the numeric registers 

Dim objRobot as FRCRobot 
Dim objNumRegs as FRCVars 
Dim objNumReg as FRCVar 
Dim objRegValue as FRCRegNumeric 
Dim lngValue as Long 

Set objRobot = New FRCRobot objRobot.Connect "robot1" 
Set objNumRegs = objRobot.RegNumerics 
Set objNumReg = objNumRegs(1) 
Set objRegValue = objNumReg.Value 
lngValue = objRegValue.RegLong

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`Example of getting the numeric registers Dim objRobot as FRCRobot Dim objNumRegs as FRCVars Dim objNumReg as FRCVar Dim objRegValue as FRCRegNumeric Dim lngValue as Long Set objRobot = New FRCRobot objRobot.Connect "robot1" Set objNumRegs = objRobot.RegNumerics Set objNumReg = objNumRegs(1) Set objRegValue = objNumReg.Value lngValue = objRegValue.RegLong

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All of this and more is available in the PCDK documentation that came with the dev kit download btw .