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Control to interpret speed as axis/button? (pedal to play!)
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rdagger:
Atmel just sent me some samples of their new AT90USB1287 AVR chips.  These will probably be the cheapest and easiest USB uC's next to PIC's.   Although I probably should not use the word easy.  Working with USB and HID descriptors is complicated and the documentation is very voluminous and unfriendly.
MonMotha:
The old Cypress chips were probably the easiest that I've seen to use.  You can actually use them without writing any of your own descriptors at all and just using a default configuration.  Unfortunately, they EOL'd them recently...without bothing to mention they were going to (they just up and did it one day).  I believe they got them from Anchor or something like that through an acquisition.

The new Cypress chips are quite a bit more difficult to use (amongst other things, the package has half the pin pitch). unfortunately.

Apparently, the Atmel USB devices aren't quite released yet.  I've talked with Atmel and they keep saying "soon", and I can get samples, but I haven't been able to coax a production release date out of them yet.
vputz:
MonMotha--

Aside from being a notable figure in the Jedi community (er, well, I thought it was "Mon Mothma", but my memory is fragile), you and rdagger made the mistake of seeming knowledgeable, so I must pester you.

See, I was hoping to avoid having to learn both "soldering tiny parts" and "programming microcontrollers" in the same project (I'd like to ensure that errors are due to either my hardware inadequacies or my coding inadequacies, but not both simultaneously)... and for that I needed a circuit which could represent itself as a HID device--and I'm willing to pay a bit extra for that.  The MJoy8 and MJoy16 could do that for me (the MJoy16 is available prebuilt) but your discussion on proper USB devices made me want to avoid the bit-banging idea even on principle.

After running across various "USB on AVR" projects and one interesting masters' thesis on connecting the AtMega chips with a philips USB chip--written in danish, so terribly helpful--I looked on Atmel's site and found a reference to their USB Key Demo Board, which incorporates an AT90USB1287 controller (nicely soldered in) and exposes all the IO pins with solder pads (solder-yer-own headers).  It looks to me like their sample software on that page includes examples of how to use the board to create HID devices (mouse and keyboard) and, well, it looks like a pretty good starting point.

And best of all, Digi-key seems to have them in stock for $31.25 (I searched for the part number, AT90USBKEY)-- which, since you can apparently upload firmware over the USB port would save me the trouble/cost of making/getting an ISP cable (I think I understand that right--via the bootloader and "FLIP"...?  There's a reference to using a JTAGS something to do programming, but I think that's different from the regular ISP, but as mentioned I'm pretty green at this).

Anyway, I don't want to pester you too much, but could one of you tell me if this is a decent starting point or if I'm way off-base?  It seems like the right product for this sort of project (even if it's a bit more than I need), but I honestly can't tell.

Thanks-->VPutz
MonMotha:
$31.25 is cheap for a dev board.  Dev/eval boards are a great way to get started with a chip for precisely the reasons you've cited.  I'd grab it and have at it if the part on it has all the features you want.

AVR parts usually have multiple methods of programming: parallel (for traditional programmers - not on all models), synchronous serial (for the smaller stuff - easily bit-banged off a parallel port), JTAG (also includes in circuit debugging), and, for USB parts, download via USB.  So you'll have your choice of how to program it.  The last option (USB) would require just the USB cable, so that's probably what you'll chose to go with, but if the part you pick has full JTAG, you may find that handy when debugging your firmware.  What will happen is that the blank chip will enumerate with a default descriptor that is just good enough to download code to the flash, then you reset it and your code boots.
vputz:
Thanks; that was the impetus I needed; I ordered two boards (this way I have a backup when I break one--and if by a miracle I don't, then I already have a project lined up for the second.  They are, it turns out, on back order (which is fine; should be available beginning of June), which gives me time to learn about the programming methods you mentioned (I'll be using the USB cable and hoping the bootloader lasts until I can learn a backup method.  The part is (I think) JTAG-capable, but I don't know squat about JTAG, so I've got some reading to do.

Thanks for the help.  Worst thing that happens is I'm out $60-$100 and learned a lot.
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