Lpc2000

tsvetanusunov <tusunov@...> schrieb am Tue, 31 Jan 2006 09:42:53 -0000:

>> Atmel already have SAM7X with embedded ethernet or at least an
>> evaluation board.
>
> ok, but what you really benefit from the embedded MAC when you anyway
> will need external PHY connected to the chip?
>
> I'll tell you from manufacturing point of view: almost nothing, no
> space saving, no price reduction, still two chip solution the price
> difference between MAC+PHY chip is just add to the SAM7S vs. SAM7X
> price.

But from the programming point an embedded MAC is easier and faster unless
you use an external MAC+Phy which completely is memory mapped.

I wonder, is there no connector with integrated Phy ?


> So why do you need SAM7X instead SAM7S+ENC28J60 for instance?
> ENC28J60 nice and small footprint taking only *few* uC ports, ohh
> yeah well it takes 250mA while running at 10Mbit... so what? I don't

Your power-regulators on the board must be layed out for this too.

> intent to use it in battery powered equipment and the power adapter
> will source these 250mA without problem, and 10Mbit cover most of
> embedded applications these microcontrollers can be used for.

What about PoE ? How much can this drive ?

> So just think again, why do you need microcontroller with only MAC
> embedded?

BTW: Freescale should present soon a Coldfire with MAC+Phy (as the NE64).


-- 
42Bastian Schick