Actually no need to build a USB stack if one is willing to use JALv2, which
has a complete USB stack, including serial and HID, in its libraries.

Check out this sample piece of code to set up an HID keyboard:

http://jallib.googlecode.com/svn/trunk/doc/html/usb_keyboard.html

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
include usb_keyboard
...
usb_keyboard_init()
...
;-- wait till USB becomes available
while ( !usb_is_configured() )  loop
end loop
...
;-- main loop
var byte ch
forever loop
;   -- call the flush routine on a regular base in the main loop
;   -- in order to keep the USB communicaiton alive
    usb_keyboard_flush()
    .....
    if ( usb_is_configured() )
       if ( pin_x )
		   ush_keyboard_send_key( 0x00, USB_KEYBOARD_KEY_A )
       else
		   ush_keyboard_send_key( 0x00, USB_KEYBOARD_KEY_NONE )
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

Doesn't get much easier than that.

BAJ


On Mon, Nov 21, 2011 at 02:04:20PM -0800, Christopher Head wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: RIPEMD160
>=20
> On Sun, 20 Nov 2011 10:17:41 -0800
> "Harold Hallikainen" <harold@hallikainen.org> wrote:
>=20
> > There are couple of ways that come to mind. Probably the simplest is
> > to use a USB to UART bridge like the Silicon Labs CP2102 and similar
> > chips from Future Technology Devices. The other approach is to use a
> > PIC with USB hardware on chip. This requires use of the USB firmware
> > provided by Microchip. Microhip provides some sample code.
>=20
> To be technically correct, it doesn't "require the use of the USB
> firmware provided by Microchip". There's nothing stopping you from
> writing your own, and the USB engine is fully documented in the
> datasheets, at least for the 18Fs. I believe a few people on this list
> have constructed their own USB stacks.
>=20
> Chris
> -----BEGIN PGP SIGNATURE-----
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> iEYEAREDAAYFAk7KyucACgkQXUF6hOTGP7dpkgCgiUM2xDuBPQQt9hoSwYI1saOB
> +7AAnRSh+fItisKXmCOh9XZuQp7+AfFt
> =3DIT5w
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>=20
> --=20
> http://www.piclist.com PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist

--=20
Byron A. Jeff
Department Chair: IT/CS/CNET
College of Information and Mathematical Sciences
Clayton State University
http://cims.clayton.edu/bjeff
--=20
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
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.