Help with USB driver and signing options

Community Projects
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I’m building a project where I would like to have a USB connection available for configuring it with a PC. This configuring will require sending data from the PC at any speed, about 2-3k worth. This project is going to be made available to a group of animated lighting enthusiasts.

For various reasons (cost, allergy to surface mount) I can’t just slap on an FTDI chip. The easy part is the USB interface (I’ll either use Microchip’s stack on a PIC or v-usb on an AVR). The challenge, however, is dealing with the driver and VID/PID. I can get a VID/PID pair from Microchip or Openmoko, and can use a standard class with existing drivers, but

Microsoft, in their infinite wisdom, now requires not only the driver to be signed, but also the inf (at least for Win 8.1 - Win 8 and Win 7 64-bit only needs signed drivers). I can’t force people to configure their PC to allow unsigned drivers just to use this project.

What options do I have, other than paying for a signing certificate? Are there any classes where PID/VID aren’t checked? I’d prefer CDC, but am ok with another class that will let this data block get passed. I guess I could always lie and use someone’s existing PID/VID and piggyback on their driver, but that’s not the best solution.

Thanks.

/mike

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Are you going to be doing all the production builds? If not then SM is easily handled by almost any assembly house.

Why not use an FTDI breakout board so you don’t need to solder the chip. For a low quantity this will work and isn’t too expensive.

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I’m producing a kit, and the people who will build it are quite allergic to SMT. Not sure why, but I don’t think I can change that. I personally prefer SMT, though the last board I did with a .4mm qfn and 0402s, and that’s my limit…

/mike

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WinUSB doesn’t require an INF or driver signing, if I remember correctly. Microchip has at least one WinUSB example in their USB Applications package, I believe. It’s very similar to a regular generic HID device, in terms of interfacing.

Make sure to get a unique VID/PID for your product. You can either buy one from USB-IF, or, if you use Microchip stuff, I think they’ll give one to you for free if you contact them.