As I mentioned before, it seems that suitable Y-cables for powering a device aren't easy to find. The cable would have to have:
- Micro A Male: goes into the password safe - USB A Male: goes into a power source - USB A Female: USB device (keyboard, etc.) plugs into this The alternative of adding a second port on the password safe itself isn't very tempting: if the power-only port is Micro B, then one could plug a Micro B cable into either port, but only one of them may work (depends also on the MCU used - some have two USB OTG devices, so they could listen on both ports.) That's kinda awkward and also eats precious space. Integrating a USB A receptacle would be a cleaner solution but that would eat even a lot more precious space. At least for the prototype, a suitable solution may be to have an external interface box with 2 x Micro B female receptacles for password safe and power and one USB A female receptacle for the USB device: http://downloads.qi-hardware.com/people/werner/pwsafe/ybox.pdf To use this, one would also need a Micro B (M) to USB A (M) cable, like the one used to connect the password safe to a PC, and a Micro A-B cable (the sort used to uinterconnect mobile phones.) Not the most elegant solution, but I think it should be okay at least for a prototype. However, if the password safe's case has to grow for any other reason _and_ the MCU has two USB ports (TBD), then it may be time to reconsider the option of adding a USB A receptacle directly in the password safe. In this case, no Micro A-B cable would be needed. - Werner _______________________________________________ Qi Hardware Discussion List Mail to list (members only): [email protected] Subscribe or Unsubscribe: http://lists.en.qi-hardware.com/mailman/listinfo/discussion
