counter Entity Reference

Upward counter. More...

Entities
Behavioural	architecture
	Architecture of the counter. More...

Libraries
ieee
	Standard library.

Use Clauses
std_logic_1164
	Standard 9-values logic library.
numeric_std
	Arithmetic library, included for the unsigned to integer conversion function.
math_real
	Standard math library, required for the log2 function.

Generics
top	natural := 64
	Maximum counter value.

Ports
clk	in std_logic
	Clock of this component.
not_rst	in std_logic
	Active-low asynchronous reset signal.
en	in std_logic
	Enable signal.
q	out std_logic
	Overflow output, asserted when the counter reaches the value top.
value	out std_logic_vector ( integer ( log2 ( real ( top - 1 ) ) ) downto 0 )
	Current counter value.

Detailed Description

Upward counter.

Upward counter with overflow and current value output

The counter value ranges from 0 to top-1

Member Data Documentation

clk

clk in std_logic

Port

Clock of this component.

en

en in std_logic

Port

Enable signal.

ieee

ieee

Library

Standard library.

math_real

math_real

Package

Standard math library, required for the log2 function.

not_rst

not_rst in std_logic

Port

Active-low asynchronous reset signal.

numeric_std

numeric_std

Package

Arithmetic library, included for the unsigned to integer conversion function.

q

q out std_logic

Port

Overflow output, asserted when the counter reaches the value top.

std_logic_1164

std_logic_1164

Package

Standard 9-values logic library.

top

top natural := 64

Generic

Maximum counter value.

value

value out std_logic_vector ( integer ( log2 ( real ( top - 1 ) ) ) downto 0 )

Port

Current counter value.