Skip site navigation (1)Skip section navigation (2)
Date:      Sun, 25 May 1997 13:23:18 +0930 (CST)
From:      Michael Smith <msmith@atrad.adelaide.edu.au>
To:        dgy@rtd.com (Don Yuniskis)
Cc:        freebsd-hackers@freefall.FreeBSD.org
Subject:   Re: diskless hardware *design* suggestions
Message-ID:  <199705250353.NAA11327@genesis.atrad.adelaide.edu.au>
In-Reply-To: <199705241622.JAA14984@seagull.rtd.com> from Don Yuniskis at "May 24, 97 09:22:29 am"

next in thread | previous in thread | raw e-mail | index | archive | help
Don Yuniskis stands accused of saying:
>     I'm hacking together an SC400 (486/66 PC on a chip) based design
> and would like that design to serve double duty as the core of an
> FBSD-based diskless system (e.g., a small X-terminal).

Hey, neat.  What VGA CRTC were you planning on using?

>     Unfortunately, none of the x86 MCU's are particularly
> tolerant of external bus masters.  And, sharing memory tends to
> clutter these designs quickly.  So, DMA is the only *painless*
> way to interface to the core.

DMA is not common with NICs.  Shared memory (usually controlled by 
the NIC) and programmed I/O are the norm.

>     As such, are there any good suggestions for NIC's that would
> fit well in this architecture?  Preferably fast ethernet?  Very
> high integration is desirable to keep the size of the box down to
> a minimum (i.e. PC/104 form factor).

There aren't a great number of fast ethernet chipsets, and even fewer
designed for tight ISA-style integration.  There is, however, a
plethora of 10Mbps chipsets that might suit; consider the Crystal
CS89x0, SMC 91cxx, NatSemi 83c90x etc.

Depending on the actual situation, you may find that the AMD PC-Net or
Intel 825xx parts are suitable too. would strongly suggest chasing the
SMC and NatSemi websites for details on any potential 100Mbps parts.

> --don

-- 
]] Mike Smith, Software Engineer        msmith@gsoft.com.au             [[
]] Genesis Software                     genesis@gsoft.com.au            [[
]] High-speed data acquisition and      (GSM mobile)     0411-222-496   [[
]] realtime instrument control.         (ph)          +61-8-8267-3493   [[
]] Unix hardware collector.             "Where are your PEZ?" The Tick  [[



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199705250353.NAA11327>