0
\$\begingroup\$

Is it possible to create an USB to micro USB (or lightning) cable that has storage built into it?

So if it's plugged into a computer with no phone, the computer recognizes it as a regular USB storage device. If it's plugged into a computer with a phone attached, it only acts as a regular USB data cable.

If is possible, is it difficult to do?

\$\endgroup\$
  • \$\begingroup\$ Certainly it's possible, and it should be no more difficult than any it her usb composite device-- straightforward if you have the right tools and experience, and difficult otherwise \$\endgroup\$ – Scott Seidman Oct 4 '15 at 14:53
  • \$\begingroup\$ @ScottSeidman Is there any way you could provide instructions on how to do it? \$\endgroup\$ – AGanz Oct 4 '15 at 16:02
  • \$\begingroup\$ As described, this is a bad idea, as connecting a phone while the storage volume is mounted would cause it to disappear without a chance for filesystem state to be flushed, which is likely to lead to data corruption sooner or later. Making a working product would require putting thought into the mode switch rules to avoid this type of issue. \$\endgroup\$ – Chris Stratton Oct 4 '15 at 18:06
  • \$\begingroup\$ @ChrisStratton Would there be any difference if I said that the cable didn't need to switch from being storage to a transfer cable when it's plugged into a phone, rather it can be both at the same time. (i.e. Is that any easier) \$\endgroup\$ – AGanz Oct 6 '15 at 22:58
1
\$\begingroup\$

Possible and difficult:

You will need an IC that can do USB storage, flash memory for that IC, and a USB switch IC. And then write some code that will switch the data lines from cable to storage IC.

\$\endgroup\$
  • \$\begingroup\$ I noticed that this product has been able to do it: symlis.com/features ....do you think this was done via the method you described above? \$\endgroup\$ – AGanz Oct 4 '15 at 14:11
  • \$\begingroup\$ No idea - get one, open it, and let us know! \$\endgroup\$ – corecode Oct 4 '15 at 14:31
  • \$\begingroup\$ If you can find their patent they mention, it will describe how it's done. \$\endgroup\$ – pjc50 Oct 4 '15 at 15:47

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.