hi steffen,
Am Dienstag, 12. September 2006 18:30 schrieb Steffen:
On 12/09/2006, at 7.14, Christian Klippel wrote:
a cheap solution is to use a parallel port [snip]
Given that the "university Mac" - mentioned earlier - hasn't been born with a parallel port, but most likely haven been born with atleast an usb port. Will a solution be as easy as getting a usb-to- parallel adapter?
well, you could go and spend some bucks for such a converter, and yes, it shoudl work.
but you can also directly use usb .... get some free samples of the pic18f2455, 2550, 4455 or 4550 from www.microchip.com you need only a few parts to make it work (namely, the usb socket, a crystal and some cap's). the first two are 28 pin devices, if you need more pins, use the latter two, they have 40 pins.
the use the PUF (Pic USB Framework) from http://vasco.gforge.enseeiht.fr/index.php?article=PUF.html
check the odyssey stuff as well, to get a diy programmer & software. dont know about mac (for the programmer part), but sdcc should compile there as well (which is needed to compile the pic source code)
thats all .... you will get an incredibly cheap usb thing with that (the cost for the socket, crystal, etc... maybe 10 bucks in total), which you can freely program in c using the sdcc compiler. once the bootloader in programmed into the pic, all further code updates are done via usb, so you need a pic-programmer only for bootstrap (initial programming of the bootloader)
I think this muct of interest for Chuckk Hubbard, but it is of my own interest aswell.
best, steffen
if there is interrest, i can do a quick schematic of that.
greets,
chris