De￿ning Traces

The OSA stores data for traces A, B, and C in reserve-memory trace arrays. These arrays comprise a series of data points (elements) that contain amplitude information. Position units describe the position of an element (point) along the horizontal axis of a trace. The point at the left end of the trace has a position-unit value of 1. The point at the right end of an 800-point trace has a position-unit value of 800. Whenever trace A, B, or C is swept, the analyzer updates the trace's array with new data. You can create your own user-de￿ned trace arrays in internal memory using the TRDEF command. Unlike traces A, B, and C, user-de￿ned traces cannot be swept.

The POSU command converts the wavelength of a point on a trace to position units. The WLU command converts a point on a trace indicated in position units to meters, or in zero-span mode, to units of time.

Prede￿ned and user-de￿ned traces can be 3 to 2048 elements. The default trace length is 800 elements. Use the TRDEF command to change the length of any trace. Use the IP or TRPST (trace preset) command to reset the lengths to their preset values. Use PURGE or DISPOSE to erase a user-de￿ned trace from internal memory.

User-de￿ned trace names can be from 1 to 12 characters long. In the following example, measurement results are transferred to a user-de￿ned trace array called TRACE Z.

10

CLEAR

723

Initialize analyzer.

20

OUTPUT

723;"IP;"

 

 

 

30

OUTPUT 723;"SNGLS;TS;"

Activate single-sweep mode and sweep

 

 

 

once.

40

OUTPUT 723;"TRDEF TRACE_Z,800;"

Create user-de￿ned trace array .

50

OUTPUT 723;"MOV TRACE_Z,TRA;"

Move copy of trace A contents into

 

 

 

TRACE

 

Z.

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