De￿ning Variables

The OSA retains in reserved memory a set of prede￿ned variables. Each prede￿ned variable stores a current OSA setting or state. Note the two characteristics of these variables:

1.Values depend on current instrument settings.

2.Names are identical with associated programming commands.

Programming commands which have the same name as a prede￿ned variable load that variable. For example, the command CENTERWL sets the OSA's center wavelength. CENTERWL also loads the prede￿ned variable CENTERWL. Prede￿ned variables reside in reserved memory and are always available to your programs. Both prede￿ned and user-de￿ned variables can be queried to return their values to the computer. Also, variables can be used as arguments to many of the OSA commands listed in chapter 8.

Partial List of Prede￿ned Variables

CENTERWL

CNVLOSS

DL

INZ

LG

MKA

MKACT

MKAL

MKAR

MKN

MKP

MKPAUSE

MKPX

MKT

MKTV

NSTATE

RB

RBR

RL

RLPOS

ROFFSET

SP

SS

ST

STARTWL

STOPWL

TH

VB

VTL WLOFFSET

 

 

 

 

 

 

Use the VARDEF command to create and store user-de￿ned variables in internal memory. User-de￿ned variable names are from 1 to 12 characters long and are assigned values immediately after VARDEF is executed. Use PURGE or DISPOSE to erase user-de￿ned variables from internal memory.

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