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Re: Unidentified subject!



Dear Jeff,

here some comments on your F21 network specs:

>>>>> "Jeff" == Jeff Fox <jfox@netcom.com> writes:

...

    Jeff> In normal operation the serial/network coprocessor will be
    Jeff> reading and echoing serial data, but it will not be making
    Jeff> any memory access.  

This is not exactly true. You are right, most of the serial port chips
don't do any memory access. But nearly all network controller do some
kind of memory access and most of them are able to do it via DMA!
(see LANCE and friends)

...

-----------------------------

You describe the network processor in some detail from the software
point of view. But there is no information about the networking from
the hardware-architectural point of view:

	o	what kind of general concept (CSMA/CD <-> token ring <-> ???)
	o	what kind of collision detect / arbitration
	o	what kind of transmission medium
	o	what max. line length (derived from the points above)


Robert