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Date   : Tue, 03 Aug 1999 10:45:44 +0100 
From   : Jon Bloomfield <Jon.Bloomfield@...>
Subject: Re: Econet hardware 

	Well, basically because the 68B54 is an obsolete part now, driving
it is quite hard work, and providing the same functions in modern technology
wouldn't actually be all that difficult.  Using a PIC certainly is an
option, but it seems like a bit of a clunky design.
It is a little clunky I agree. The reason for considering PIC is that I
would prefer to keep the interface external to the PC. That means either
serial, or parallel connections, and the PIC range has good support for
these. Using a serial interface probably means restricting the network speed
to about 115k, but I can live with that. My PC accepts up to 921k for the
serial port baud rate, so there is a sporting chance of driving higher than
115k, but I'm not daft enough to rely on this.
How fast can the BBC really drive the network in practice ? I know the clock
boxes can drive up to about 600k, but I would imagine that the CPU would
have trouble driving much above 115k anyway. 

	Fair enough, I guess.  If I were you in that case I think I'd do
what Mark said and use one of the ready-built plugin modules.  You can
probably buy them secondhand for less than the cost of the component parts,
and this saves you the hassle of worrying about the analogue side of things
(which I have a vague recollection was a bit marginal on the BBC).

Sounds like a good plan - As I said, I'm really a software engineer, so my
analogue electronics is basic in the extreme.
 
Anyone know where I can get hold of a master econet module ? I have been
offered one already, but I'll need two if I'm gonna use it for both PC and
my BBC Master.

Thanks

Jon 

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