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EBX spec problem

Started by rickman August 13, 2006
I was looking at the EBX specification and it appears that they have
located the PC/104 mount very close to the PCMCIA mount.  I don't see
where you would be able to fit connectors and such in the space between
them that the PC/104 spec allows for.  The copy of the EBX spec I
downloaded has a very poor mechanical drawing and is missing a lot of
details such as mounting holes and spacing between components so I
can't tell for sure.

Anyone know if EBX allows for the connector overhang that is called out
in the PC/104 spec?  Anyone know what happened with the mechanical
drawing in the EBX spec, why is it unfinished or corrupted?

I remember back with version 2.1 or so of the PC/104 spec that the
mechanical drawing PDF file had a problem where the crosshatch for the
IO region covered nearly the whole board.  It was as if the DXF to PDF
conversion had a problem and no one at the consortium ever proofed it
before posting it to the web site.  Now it would appear that the EBX
spec has a similar shortcoming.  Is this going to be typical of their
publications in the future?

I just noticed that on the web page where they answer the question,
"What is PC/104?", they have technical mistakes...

http://www.pc104.org/technology/reg_info.html

They list the bus drive as 6 mA instead of 4 mA as the spec calls out.
The first diagram shows the board to board spacing of 0.6" being from
bottom to bottom rather than top to bottom.  The spec and the diagram
shown later on this page clearly show the 0.6 inch dimension being the
space between boards or in other words the height of the spacer.

I guess none of this is critical in any way since the spec would take
precedence, but it just seems very sloppy.  I guess in the grand scheme
of things they are documenting the bus a lot better than IEEE did the
ISA bus in the first place.  IEEE started a standardization effort and
even produced a draft, but I can find neither hide nor hair of it now.
Ed Solari's book is the stated bus standard in the current PC/104 spec.
 

I just don't like working with sloppy standards.  :^(