topic Re: USBD_STATUS_CANCELED in USB bulk transfer in i.MX RT Crossover MCUs

USBD_STATUS_CANCELED in USB bulk transfer

ingdb — Mon, 30 Jan 2023 17:11:33 GMT

Dear all,

we're working on a RT1176 and we're testing USB communication

the firmware code is quite simple, we're using bulk transfer

uint8_t WriteUsb(const uint8_t *data, uint32_t size) { usb_status_t error = kStatus_USB_Error; error = USB_DeviceCdcAcmSend(s_UsbInterface0CicVcom.cdcAcmHandle, USB_DIC_VCOM_IN_ENDPOINT, data, size); if (error != kStatus_USB_Success) { if (error != kStatus_USB_Busy) PRINTF("kStatus :%d \n", error); return false; } return true; } #define bufSize 126 void DirectStream() { uint16_t val = 0; while (1) { static uint8_t buf[bufSize]; for (int i = 0; i < 7500; i++) { for (int j = 0; j < bufSize; j += 2) { memcpy(buf + j, &val, 2); val++; } while (WriteUsb(buf, bufSize) == 0); } } }

We're receiving and verifying the data on a Windows and Linux PC, but for both systems, we have after some seconds a USBD_STATUS_CANCELLED error.

I am trying to understand this behavior, I found indications that this could be caused by the host PC but I am not sure if it's firmware related. The USB_DeviceCdcAcmSend function never returns an error (except kStatus_USB_Busy).

Can anyone shed some light on this?

best regards

Matthias

Re: USBD_STATUS_CANCELED in USB bulk transfer

Omar_Anguiano — Thu, 09 Feb 2023 23:15:08 GMT

Hello
Hope you are well.

To check if this issue is caused by the firmware or the host I suggest you test it with one of our SDK examples.
USB_DeviceCdcAcmSend checks whether the endpoint is sending a packet if the pipe is busy, it ignores this transfer by returning an error code.

Best regards,
Omar

Re: USBD_STATUS_CANCELED in USB bulk transfer

ingdb — Fri, 10 Feb 2023 08:06:21 GMT

Hello Omar,

thanks for your help.

I am using an SDK example as the base but as NXP doesn't have a streaming example I modified it a little bit. The normal non streaming SDK examples are running but that's an entire different use case, I can't draw conclusions from that.

Yes, USB_DeviceCdcAcmSend returns error codes, I am receiving ONLY kStatus_USB_Busy (that's making sense) but no other error code.

best regards

Matthias