[Gmecm] Any USB developers out there?

[Steve Ravet]

> -----Original Message-----
> From: gmecm-bounces at diy-efi.org 
> [mailto:gmecm-bounces at diy-efi.org] On Behalf Of Craig Moates
> Sent: Thursday, November 09, 2006 11:51 AM
> To: gmecm at diy-efi.org
> Subject: Re: [Gmecm] Any USB developers out there?
> 
> Steve,
> 
> Definitely check the crystal and capacitor areas. Those are 
> ceramics you are using for the 18pF set? Check that it's set 
> up for 18pf on the xtal desired capacitance?

The crystal is 20 MHz 18pf according to the digikey datasheet.  They're
ceramic caps.

I don't know what the problem with the crystal circuit is, but I removed
it and used a 4 MHz OSC instead, changing the firmware accordingly, and
now it works.  I tried with and without the load resistor (on the
crystal) but no change.  The demo board has an external load resistor
but the data sheet shows a resistor internal to the part.

I decided that I want USB power after all so I can reflash the PIC
without external power.  You mentioned the circuit you use but I can't
find the note now.  What is it?

Craig, what do you use for schematic capture and PCB layout?

Maybe there'll be a USB <-> VPW project working by Christmas now...

thanks for the suggestions everyone,

--steve