USB CDC Read, cancelling when timeout occurs

[mugsimar]

How do I cancel ucb_cdc_acm_read?

What I want to do is if a timeout occurs, and APP_USBD_CDC_ACM_USER_EVT_RX_DONE has not been triggered, then I should be able to cancel app_usbd_cdc_acm_read, and reset it to a read size of 1 in order to make sure that after receiving one symbol, APP_USBD_CDC_ACM_USER_EVT_RX_DONE  will be triggered.

[Amanda Hsieh]

Hi, 

Sorry for the delay. I am checking with the internal and will get back soon if I have anything. 

Regards, 
Amanda

[Amanda Hsieh]

Hi, 

Could you elaborate on your need? Maybe present to us your use case? We already have non-blocking API in CDC ACM (app_usbd_cdc_acm_read_any and app_usbd_cdc_acm_rx_size functions) that should do what you need. You wouldn't need to use the blocking API then cancel it.

-Amanda

[mugsimar]

Hi Amanda,

Our usecase is, usb seems to be using DMA, I'm sending fixed number(255) of bytes from PC to NRF. What I want is, incase the the host pc failed to send 255 bytes, let's say only manage to send 250, a timeout will trigger and will reset the usb_cdc_read. howeverer, calling another usb_cdc_read doesn't seem to work. 

Thanks,

Miguel

[Priyanka]

Hi Miguel,

Sorry for the delay since it's the Holiday month. We have conveyed this to the experts and will get back to you soon regarding this issue

Regards,

Priyanka