Mario,

> Microchip have specification sheets available on a couple of parts
> (16c745/765), but they are still listed as future products. Perhaps
> someone can any recommend another architecture? I have heard that
> Cypress USB MCUs have 50% of the USB market at this time; anyone have
> any experience with them? I have seen Phillips mentioned a couple of
> times too I think; any comments?

It really depends upon your design, and what you currently know and
love.

I've recently started connecting the Philip's PDIUSBD11 (USB Interface
Device with Serial Interface) to Microchip's 16F877. This allows the
ability to use USB on your favorite PIC architecture. The 16F877 has
the Master I2C Synchronous Serial Port, thus I've hanged the PDIUSBD11
of that.

This design is going along quite well, minus a little set back with
erratic programming of the PIC16F877 which is driving me up the wall.

Previously, I used the Cypress CY7C63001 packaged in the popular USB
Starter Kit (CY3640). Not being familiar with the instruction set or
architecture on this beast, I spent a little while learning a new
device. This didn't pay of at the end, as I dumped the Cypress
Controller for other reasons. Most of the Cypress parts are Windowed
EPROM Parts.

I must say, I've always been a Motorola Person thus I looked in this
direction (68HC705JB4 / JB4). I could never source them. . . . . That
fixed that. Speaking of sourcing components, I also found the Philips
hard to come by. I ended up buying a MOQ of 22 pcs.

The Motorola and Cypress alternatives have very little in the range of
emulators / debugging.

If you already have the development tools for the PIC's and the
knowledge, I would consider dropping a PDIUSBD11 off it's I2C Port. Fair
Enough, the USB registers aren't mapped into memory like the Cypress and
Motorola USB MCU's and there is a little (read considerable) overhead
regarding the 1MBit/s I2C Serial Interface but it's definitely a good
starting point. Plus, if you choose the 16F8xx you have the ICD to help
you along and the advantage of a Flash device. (I don't let know if it's
wise to recommend the F87x parts.)

The other advantage is, provided you take a modular approach to your
code, you can develop it now for the PDIUSBD11 and when Microchip
releases their USB MCU's you can modify the low level routines to use
the new devices.

Regards,

Craig Peacock
______________________________________________________________

Interfacing the PC -
Information on Serial / RS232 Ports, Parallel, ECP, EPP
Ports, IRQ's, and AT Keyboards, USB & Device Drivers.
http://www.senet.com.au/~cpeacock
______________________________________________________________