FPGA Central

Would anyone here know the history of pin B3 on the pci express
connector?

The latest PCISIG document shows it as +12V with no change bar
associated with it. However I have found reference designs with it
labelled as reserved. I can put a zero ohm link on it for development
but sooner or later I have to work out what is compatible with all
motherboards out there.

regards

Colin

On Wed, 25 Jul 2007 02:00:39 -0700, colin <[email protected]>
wrote:

>Would anyone here know the history of pin B3 on the pci express
>connector?
>
>The latest PCISIG document shows it as +12V with no change bar
>associated with it. However I have found reference designs with it
>labelled as reserved. I can put a zero ohm link on it for development
>but sooner or later I have to work out what is compatible with all
>motherboards out there.

The 1.0 electromechanical spec (from April 2003) shows it as reserved;
it was changed in the 1.1 spec (March 2005) to +12V. None of the other
reserved pins were changed. I would just connect it directly to your
other +12V pins.

Evan

On 25 Jul, 13:35, Evan Lavelle <nos...@nospam.com> wrote:
> On Wed, 25 Jul 2007 02:00:39 -0700, colin <colin_toog...@yahoo.com>
> wrote:
>
> >Would anyone here know the history of pin B3 on the pci express
> >connector?
>
> >The latest PCISIG document shows it as +12V with no change bar
> >associated with it. However I have found reference designs with it
> >labelled as reserved. I can put a zero ohm link on it for development
> >but sooner or later I have to work out what is compatible with all
> >motherboards out there.
>
> The 1.0 electromechanical spec (from April 2003) shows it as reserved;
> it was changed in the 1.1 spec (March 2005) to +12V. None of the other
> reserved pins were changed. I would just connect it directly to your
> other +12V pins.
>
> Evan

Evan

Many thanks for this info. I allways feel silly asking this sort of
question but I could only find version 2.0 on the PCISIG website.

Regards

Colin

On 2007-07-25, colin <[email protected]> wrote:
>
> Many thanks for this info. I allways feel silly asking this sort of
> question but I could only find version 2.0 on the PCISIG website.

I haven't tried this with PCI-e, but for PCI I found a complete copy
of several versions by googling for the exact title (in quotes) along
with filetypedf to restrict the results.

--
Ben Jackson AD7GD
<[email protected]>
http://www.ben.com/