2019-12-17 03:15 PM
I need a 2-port host that can bridge 2 CDC slaves. What is the best chip for doing this? I don't want to spend much time doing software development like writing CDC drivers.
2019-12-18 02:46 PM
Two ports, meaning two separate USB bus connections, will require at least an STM32F7 class controller. M4 based STM32s only have a single USB port. Not sure if the Cube (or whatever it's called this month) supports two separate CDC instances. Since it's a host you'll need OTG capability.
If you don;t want to develop code you might be better off looking at a Linux distribution on a Cortex A series application processor rather than an M series controller.
Jack Peacock
2019-12-18 02:52 PM
Thank you. I think STM32F7 is too much for this simple bridging application. I am looking at the FTDI VNC2 which seems to work but it is a very old chip.
2019-12-18 03:34 PM
> Two ports, meaning two separate USB bus connections, will require at least an STM32F7 class controller. M4 based STM32s only have a single USB port.
Nope, there are STM32F4's with two USB host/OTG controllers. Maybe L4 too.
Some of these USB IP can even support hubs (several devices on a single host port), but this is quirky and obscure.
-- pa
2019-12-18 06:47 PM
Whats the clues for running a hub ?