Freeze Counter Block

Block: Freeze Counter Block (freeze_cntr)
Block Author: Aaron Parsons
Document Author: Aaron Parsons

Contents

Summary
Mask Parameters
Ports
Description

Summary

A freeze counter is an enabled counter which holds its final value (regardless of enables) until it is reset.

Mask Parameters

Parameter	Variable	Description
Counter Length (2^?)	CounterBits	Specifies the number of bits (and the final count output of 2^{bits − 1}).

Ports

Port	Dir	Data Type	Description
en	in	???	Step the counter by 1 unless addr=2^{bits − 1}.
rst	in	???	Reset counter to 0.
addr	out	???	Current output of the counter.
we	out	Boolean	Outputs boolean true just before addr is incremented.
done	out	Boolean	Outputs boolean true when a final en is asserted and addr=2^{bits − 1}.

Description

A freeze counter is an enabled counter which holds its final value (regardless of enables) until it is reset. Thus, a 2⁵ freeze counter will count from 0 to 31 on 31 enables, but will hold 31 thereafter until a reset occurs. This block is useful for writing data in a single pass to memory without looping.