JDS Uniphase RM3750 user manual Command Action

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RM3 SERIES BACKREFLECTION METER

USER’S MANUAL

On power-up, the RTS and DTR signals on the interface connector go positive, indicating that the interface is ready to communicate. The software on the controlling computer must enable the RTS line. The interface controller waits for the CTS line to go positive before the measurements are transmitted. The DCD line must go positive in order for the controlling computer to receive commands from the meter.

The meter responds to single character commands sent on the serial interface. The characters must be sent individually, without a message terminating sequence such as <CR> (carriage return) or <LF> (line feed). The meter acknowledges each character that is sent with a character or a measurement reading.

The command G initiates the transmission of a measurement. The meter returns the most recent measurement. The transmission also includes the wavelength at which the measurement was made and the characters <CR> <LF>.

The character commands that control the meter via the RS232 serial interface port are listed in Table 9. When a command is accepted, the letter Y is returned. When a command is not recognized or not accepted, the letter X is returned.

Table 9: Character Commands

Command	Action

B	Display backreflection

A	Display absolute power

R	Display relative power

S	Store BR0 1

C	Clear BR01

D	Store ID 2

0	Set relative power to zero3

3	Set wavelength to the laser connected to the first LED
	on display (eg. Model RM3750, first laser=1310nm. See
	Figure 3)

5	Set wavelength to the laser connected to the second
	LED on display (eg. Model RM3750, second
	laser=1550nm. See Figure 3)

1Valid in Backreflection mode only.

2Valid in Absolute Power and Relative Power modes only.

3Valid in Relative Power mode only.

10112341 Rev 002

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Contents RM3 Series Backreflection Meter User’s ManualContents Customized Features and Test Data Programming GuideSafety Information, Instructions, and Symbols Safety InformationClass Laser Product Operating the Unit Safety InstructionsBefore Initializing and Operating the Unit RM3 Series Backreflection Meter USER’S Manual Proceeding Safety SymbolsSymbol FDA-CDRH Compliance CSA / IEC Compliance ComplianceCE Compliance RM3 Series Backreflection Meter USER’S Manual General Information and Specifications General InformationLoss and Power Measurements Backreflection MeasurementsInternal Light Sources Key FeaturesOutput Port Hybrid JumpersApplications Standard AccessoriesOptional Accessories Specifications Parameter Specification Single-mode MultimodeFlexcor is a trademark of CorningR Environmental ElectricalPhysical Initial Inspection Getting StartedBefore Initializing and Operating the Unit Operating Environment Storing and ShippingCleaning Connectors Powering Up the Meter Connector Cleaning connector type can varyKey/LED Description Operating and Maintenance InstructionsFront Panel Component Function Rear PanelTermination Techniques Termination Techniques for Single-mode Fiber except 980 nmMeasuring Backreflection for Single-mode except 980 nm Setting Up the Meter for Backreflection Measurements Backreflection MeasurementsMeasuring Backreflection Backreflection Accuracy and Range Loss and Power MeasurementsSetting Up the Meter for Loss and Power Measurements Measuring Power Loss and Power MeasurementsMeasuring Relative Power Insertion Loss Measuring Absolute PowerPower Accuracy Data Logging Using the Foot PedalMessages and Symbols Display DescriptionCalibrating the Meter StabilizingBackreflection Calibration Adjustment Power Calibration AdjustmentMaintaining the Meter Cleaning the UnitCleaning the Connector Ends Troubleshooting Recharging the BatteryReplacement of Internal Fuses Loss Before the DUT Front Panel Connectors Long Cables for single mode model only, except 980 nm model Reflections Before the DUTCalibration Other Display Problem SolutionLaser Stability Up the Meter for BackreflectionProgramming Guide RS232 Interface SpecificationsName Symbol Pin Number Signal Direction RS232 Serial InterfaceCommand Action Right Dip Switch Left Dip SwitchSwitch Setting Meaning RS232-GPIB ConverterProgramming Examples RS232 Interface Program ExampleCustomized Features and Test Data