Instruction manual

Integer Compares

890USE18300 September 2003

Inside-the-window Integer Compare Block

Summary An inside-the-window integer compare block performs a comparison between an

analog input value and a window bounded by two thresholds. The input value is

represented as an integer in the range -32 768 to +32 767. The software lets you

assign values to the two thresholds (TH 1 and TH 2) along with a delta (∆) value,

which acts as an hysteresis around TH 1 and TH 2. The block produces a Boolean

result as its output.

Structure of an

Inside-the-

window

Compare Block

A block diagram for an inside-the-window integer compare is shown below:

The block has two inputs—an enable input and one operational input. The enable

input turns the block on or off. The operational input sends a word value to the block

that will be compared against the thresholds.

The block also has three preset values (See Configuring Preset Values for a Reflex

Block, p. 27)—TH 1, TH 2 and a ∆ for hysteresis around the TH 1 and TH 2 values.

The range of values between TH 1 - ∆ and TH 2 + ∆ comprises the window against

which the operational input value will be compared. You must specify these presets.

The output is a Boolean 1 when the operational input value is inside the window

(greater than TH1 + ∆ but less than TH2 - ∆) and a Boolean 0 when the input value

is not inside the window (less than or equal to TH1 - ∆ or greater than or equal to

TH2 + ∆). The output remains unchanged when the operational input is greater than

TH1 - ∆ but less than or equal to TH1 + ∆, or when it is greater than or equal to TH2 -

∆ but less than TH2 + ∆.

output

enable

operational input

inside-the-window compare

threshold 1 +/-

∆

threshold 2 +/-

∆