[SI-LIST] Re: [SI-LIST]: Wired-AND VS Wired-OR logic

Hello Anand,

ECL family can be used in wired-OR fashion. 
Outputs of different gates can be tied together 
to one common resistor to VEE. The value of 
this resistor depends on the number of outputs 
connected.

Regards,

Sunil

On Wed, 24 Apr 2002 Anand.Kuriakose@xxxxxxxxxx wrote:

> 
> 
> 
> Hi all,
> 
> We can introduce wired-AND logic by connecting 2 or more open-drain (also
> open-collector) outputs together with a single pull-up resister. The logic of
> AND logic results as follows: If one or more of the drivers asserts the output
> to low state (electrically low ), the equivalent output is low, which is how 
> an
> AND gate functions. Also the connected signals have to be active-low signals.
> 
> I have seen many documents refering to the above scenario as wired-OR logic. 
> It
> doesnt make sense. Also the PCI spec 2.2, sec2.1 refers to O/D signals (ex 
> INTX#
> and SERR#) as to be capable of introducing wired-OR logic.
> 
> So what is wired-OR logic? How do we realise this logic? Does the active level
> of the connected signals make the difference?
> 
> Also one more question.  When it comes to wired-AND logic, only one device can
> assert its output low. We cannot have more than one device asserting its 
> output
> low simultaneously. Am i right in saying so. If yes, is this allowed in 
> wired-OR
> logic.
> 
> Thanx in advance for all the valuable inputs.
> 
> Regards,
> Anand Kuriakose.
> 
> 
> ------------------------------------------------------------------
> To unsubscribe from si-list:
> si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field
> 
> or to administer your membership from a web page, go to:
> http://www.freelists.org/webpage/si-list
> 
> For help:
> si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field
> 
> List archives are viewable at:     
>               http://www.freelists.org/archives/si-list
> or at our remote archives:
>               http://groups.yahoo.com/group/si-list/messages 
> Old (prior to June 6, 2001) list archives are viewable at:
>               http://www.qsl.net/wb6tpu
>   
> 
> 

------------------------------------------------------------------
To unsubscribe from si-list:
si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field

or to administer your membership from a web page, go to:
http://www.freelists.org/webpage/si-list

For help:
si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field

List archives are viewable at:     
                http://www.freelists.org/archives/si-list
or at our remote archives:
                http://groups.yahoo.com/group/si-list/messages 
Old (prior to June 6, 2001) list archives are viewable at:
                http://www.qsl.net/wb6tpu

Other related posts: