On Wed, 12 Mar 2003 02:33:21 -0800, you wrote:

>> could you suggest me a micro featuring over 70 I/O, uart, with decent
>> delevopment tools? (easy uh?)
>> always for my "MIDI thing" project

There is a reason you only see lots of I/O on large, expensive chips.=20
The cost of a chip is mostly dependent on die size, and this in turn =
depends on 2 things - the
amount of circuitry, and the space required for the bond-out pads, which =
are usually around the
edge.=20
If you have a relatively small amount of circuitry, e.g. a low end PIC or=
 small FPGA, but lots of
I/O, the size of the chip becomes determined by the number of bond pads, =
and you end up with wasted
space at the centre of the chip, so the extra I/Os add a disproportionate=
 cost due to the die size
required to bond them out.
There is also the issue of the cost of bonding and testing large numbers =
of pins.=20
You can clearly see this on FPGAs, where pin count increases with gate =
count and cost.=20

So the bottom line is if you want a low to mid-range micro and zillions =
of I/Os, the most
cost-effective way to do it is with external latches etc. for I/O =
expansion.=20

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