User`s guide

1-11

Introduction to Programming

Program Data Syntax Rules

Prog ram data is used to convey a par am eter information related to the com mand

header. At least one space must separate the command header or query header

from the program data.

When a program mnemonic or query has multiple program data, a comma

separates sequential program data.

For example, :CHANNEL:THRESHOLD POD1,TTL has two program data:

POD1 and TTL.

Two main types of program data are used in commands: character and numeric.

Character Program Data

Character program data is used to convey parameter information as alpha or

alphanumeric strings. For example, the :TIMEBASE:MODE command can be

set to normal, delayed, XY, or ROLL. The character program data in this case

may be NORMAL, DELAYED, XY, or roll. The command :TIMEBASE:MODE

DELAYED sets the time base mode to delayed.

The available mnemonics for character program data are always included with

the instruction’s syntax definition. See the online Programmer’s Reference for

more information. When sending commands, you may either the long form or

short form (if one exists). Uppercase and lowercase letters may be mixed freely.

When receiving query responses, uppercase letters are used exclusively.

Numeric Program Data

Some command headers require program data to be expressed numerically. For

example, :TIMEBASE:RANGE requires the desired full scale range to be

expressed numerically.

For numeric program data, you have the option of using exponential notation

or using suffix multipliers to indicate the numeric value. The following numbers

are all equal:

28 = 0.28E2 = 280e-1 = 28000m = 0.028K = 28e-3K.

When a syntax definition specifies that a number is an integer, that means that

the number should be whole. Any fractional part be ignored, truncating the

number. Numeric data parameters accept fractional values are called real

numbers.