Re: slew filter arguments

Xavier Bestel wrote:

>Hi,
>
>just a little remark about the slew filter: when absent, the negative
>slope is said to be the "inverse" of the positive slope, whereas it
>should probably be the "opposite".
>  
>

Hi

I have another remark to add to the slew description. In the 2.3 draft 
LRM it says

"If the rate of change of expr is less than the specified maximum slew 
rates, slew() returns the value of expr."

My literal interpretation of this is that if the signal is slewed, then 
as soon as the input expression slope falls below the maximum slew rate, 
the slewed output will jump from its slewed value to that of the imput 
expression.

To me, this isn't what I'd expect from slew. I would expect that the 
output of slew(), once it is slewed, to continue rising/falling at the 
slew rate until it catches up with the input expression (either because 
the input flattens out, or because the input drops/rises to rejoin the 
slewed output). Thus for a slewed signal, it is the delta between the 
slewed output and the input expression that counts.

Regards
Paul
-- 
Dr Paul Floyd
Mentor Graphics Corporation


-- 
This message has been scanned for viruses and
dangerous content by MailScanner, and is
believed to be clean.