Achronix Speedster22i User Macro Guide Instrukcja Użytkownika Pobierz pdf (Strona 101)

Speedster Macro Cell Library AchronixSemiconductorProprietary PAGE 84

Chapter 4 – Lookup Table (LUT) Functions

LUT4

Four Input Lookup Table

din0

LUT4

din1

din2

din3

Figure 4-1: Logic Symbol

LUT4impl

ementsafour‐inputlookuptablewithdatainputs(din0‐din3)anddataoutput(q),

whosefunctionisdefinedby thesixteen‐bitlut_functionparameter.TheLUT4istreatedasa

black‐box by the synthesis tools. The user may inst antiate this block to define specific

structuresoflogicfunctions.

Pins

Table 4-1: Pin Descriptions

Name Type Description

din0 - din3 Data inputs.

Data output. T

he value on dout is the bit of the lut_function parameter

indexed by the inputs {din3,din2,din1,din0}.

Parameters

Table 4-2: Parameters

Parameter Defined Values Default Value

lut_function 16’h0

lut_function

Thelut_functionparameterdefinesthevalueontheqoutputoftheLUT4asdetailedinTable

4‐3: FunctionTable.Thede

faultvalueofthelut_functionparameteris16’h0.

input

output

16-bit hexadecimal value

1 2 ... 96 97 98 99 100 101 102 103 104 105 106 ... 223 224

Brak uwag

Achronix Speedster22i User Macro Guide Instrukcja Użytkownika Strona 101