How would you talk to USB CDC serial port from IOS?

[Andrei Chichak]

I've got an STM32F7 device set up as a CDC virtual com port, and I have Windows, MacOS, and Linux talking to it. The device side works nicely, I'm wondering about the iPad side.

I was wondering if there is some sort of framework within IOS/Xcode that would make the VCP available. We've tried a few avenues, and IOS does speak USB CDC but things like ethernet not serial.

Has anybody got something like this working?

Thanks,

Andrei from The Great White North.

[Romain LE DONGE]

Hello Andrei

You're right, as of today iOS does not let you talk directly through USB Serial via its lightning connector

Maybe there is a workaround. You can get inspired by :

• https://github.com/rsms/peertalk that does "USB communication" between iOS and macOS via lightning (this is used by Duet the desktop extending app)
• https://github.com/fetisov/lrndis which is described as "stm32 ethernet over usb (rndis + lwip)", but I haven't tested it

If you find a solution to do communication between STM32 and an iOS app, i am also interested :)

Best regards,

Romain