Formatting Trace-Data Output

The trace-data format (TDF) command controls the format of trace-amplitude data output from the OSA. All the available format modes return amplitude information in measurement units except for TDF P, which returns parameter units. The output formats are summarized in the following table. (Parenthetical numbers in the table are decimal values representing binary, 8-bit numbers.)

Trace Data Output Formats for Amplitude Information

Format

 

 

 

 

 

 

 

OSA Output

 

 

 

 

 

 

Trace Element Output

Command

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Amplitude of +10 dBm

 

 

 

 

 

 

 

 

 

 

 

 

TDF

P

Returns

ASCII

decimal

 

value. Values

are in

parameter

units.

Data

+10.00

 

 

output

is

followed

by

line feed (ASCII

code

10)

and

 

 

 

 

 

 

 

end-or-identify (EOI)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TDF

M

Returns

ASCII

integer

value. Values

are

in

measurement

units.

+1000

 

 

Line feed (ASCII code 10) and EOI follow data output.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TDF

B

Returns

binary

 

value

as one or two 8-bit bytes

(determined

by

(3) (232)

 

 

the MDS

command),

with most signi￿cant

byte

￿rst.

Values are

 

 

 

 

in measurement

units.

Sends EOI with

last

byte.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TDF

A

Sends

series of

one or

two 8-bit bytes

(A-block

data

￿eld

and

(#)(A)

(0)(2) (3)(232)

 

 

the number of

 

bytes

is

determined

by

the

MDS

command).

Data

 

 

 

 

is preceded by

 

\#" and

\A" and two

bytes

representing

length of

 

 

 

 

data ￿eld.

Values

are

in measurement

units.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TDF I

Sends a series

of

one

or two 8-bit b

 

ytes (I-block

data

￿eld and

(#)(I)

(3) (232)

 

 

the number of b ytes is determined b

 

y the MDS command). Data

 

 

 

 

is preceded b y \#" and \I". V alues are in measurement units.

 

 

 

 

 

Sends EOI

with

 

last b

yte.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TDF P formats data as ASCII, decimal values in parameter units. Instrument preset (IP) activates the TDF P format, and the AUNITS (amplitude units) command speci￿es the kind of parameter units. The default units are volts for linear trace information and dBm for logarithmic trace information. A line feed (ASCII code 10) follows data output. The end-or-identify state (EOI) is sent with line feed. The TDF P format is convenient because it returns parameter-unit values, but it is the slowest of the data-format modes.

2-10