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Date: Sat, 24 May 1997 21:31:22 +0300 (EEST)
From: Narvi <narvi@haldjas.folklore.ee>
To: Don Yuniskis <dgy@rtd.com>
cc: FreeBSD hackers <freebsd-hackers@freefall.FreeBSD.org>
Subject: Re: diskless hardware *design* suggestions
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On Sat, 24 May 1997, Don Yuniskis wrote:

> Greetings!
>     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, you get to write the BIOS! :-) Unless, of course you opt to use one
distributed by AMD with the evaluation board.

>     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.
>     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).

I am not sure if Fast ethernet is very usable with a 486/66 and no bus
mastering. But take a look at the SMC FEAST controller (91C100), it has
32/16 bit bus support and is not meant specificly for PCI (actually, VL is
even mentioned). For 10 Mbit ethernet SMC also makes single-chip thingies
with direct ISA interface (91c94 - 91c96). They have 4.5KB RAM
on-board (dynamically allocated, in which upto 18 packets may be stored
at a time). There even seems to be enough information for writing a
driver. 

	Sander

>     Thx!
> --don
>