USB-CDC to uart with RTS/CTS flow control

1099789860 — Thu, 16 Apr 2020 06:25:02 GMT

I am currently in routine use usb_device_composite_cdc_vcom_cdc_vcom，I would like to implement hardware flow control by RTS & CTS。At present, for control of RTS I found a way，that is to deal with SetControlLineState class request,it is to deal with kUSB_DeviceCdcEventSetControlLineState in sdk。Problems encountered now is how to achieve control of CTS，I did not find the appropriate interfaces in the sdk? And 《Universal Serial Bus Class Definitions for Communication Devices》 also not part of the description cts，we can find a request for RTS in this specification is SetControlLineState，but it does not mention the part cts，whether it can support CTS flow control？

Assume USB-cdc support CTS, then if there is a corresponding interface in the SDK?How to deal with the cts in usb_device_composite_cdc_vcom_cdc_vcom?

Looking forward to your reply!

Re: USB-CDC to uart with RTS/CTS flow control

Alexis_A — Fri, 24 Apr 2020 16:55:00 GMT

Hello,

As you notice the only control lines handle by the CDC stack are only RTS and DTR, but as the USB communication works, I think these lines aren't necessary. The coordination between the host and the device will be done by the control endpoint (endpoint 0) so if the device needs to send a transmission or a reception the respective Token will be sent.

Let me know if this helps you.

Best Regards,

Alexis Andalon

MCUXpresso SDKのトピックUSB-CDC to uart with RTS/CTS flow control

USB-CDC to uart with RTS/CTS flow control

Re: USB-CDC to uart with RTS/CTS flow control