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PIC-USB Host

Posted: Sat Nov 20, 2004 2:22 am
by SOI_Sentinel
This is a warning: I see "New Product Ideas" forums as "Here's a place to go slightly wild!".

(I'm also bored at work, but it pays the bills)

OK, now the topic of this thread will freak a lot of people out. Hear me out first.

Many of the new "big pics" in TQFP-80 packages have an external memory bus interface finally. The mega 144K versions only run at 25MHz max, while the smaller 64K versions run at 40MHz. Now, we take the 40MHz version (say, a PIC18F8680, and interface it with a Cypress SL811HS Host Slave Controller.

PIC18F8680
http://www.microchip.com/stellent/idcpl ... e=en010325

SL811HS
http://www.cypress.com/products/datashe ... E3F02A4D81

Now, the SL811HS's acts as a memory mapped peripheral, and look here, there's memory mapping on the PIC! The cypress chip does both master and slave mode, too, so it's a master when connected to a network without a master, and a slave when connected to your PC.

Now, I'm personally not working on any PC peripherals right now. However, this PIC can handle the off-chip memory interface someone else wanted a year ago (to the 2MB limit), it's a PIC doing the USB instead of a 16 bit microcontroller as the FX2 family and the EZ Host 16 bit standalone/coprocessor.

EZ Host
http://www.cypress.com/products/family. ... st#tabdata

Now, all we need is some mass storage PIC code or a nice USB reader for a webcam, and we'd be set :)

Posted: Sat Jan 22, 2005 9:37 pm
by Guest
Why not keep it simple and use one of the new usb
18f pics
http://www.microchip.com/ParamChartSear ... &pageId=74
Only usb fullspeed(not high speed)
but they run at 48MHz and have plenty of flash.
18F4550 http://www.microchip.com/stellent/idcpl ... e=en010300[/url]

Posted: Sat Jan 22, 2005 10:06 pm
by SOI_Sentinel
That was posted 2 months ago. :) They hadn't even announced the USB PIC's at that time. Anyway, Sparkfun already carries the chips.

Anyway, pairing the SL811HS with a 40 Mhz big pic like the new 18F8722 still has some advantages. It still has master mode, which may or may not be useful to some. Otherwise, I too would go with the integrated !8FX550 solutions.