Hi,
I'm trying to add the USB MSC component to a device that already implements the USB Custom Class component. The MSC component works fine, but the Custom Class component stopped working. Can anybody confirm that my combination of USB device classes works?
I've checked that the RTX RTOS is configured correctly and the USB threads run. Other users in the forum had the problem that threads didn't launch due to insufficient memory.
When I move the MSC component to an other USB instance (USBD_Config_MSC_0.h/USBD_MSC0_DEV == 1) the Custom Class component works again. My device has only a single USB port, so this isn't an option though.
I've used the Windows Device Manager to analyze the Problem. Curiously both device classes are displayed, but I'm no longer able to connect to the device via my custom service tool.
Has anybody had similar issues, or knows how I could further debug the problem?
Best,
Valentin
Hi Milorad,
thank you for pointing that out. I've analyzed our source code and found that libusb_open_device_with_vid_pid is used to connect to the USB device. In the case of a composite device two USB devices with identical vid and pid appear. Most likely the function can't handle this situation (although I can't confirm that). Using libusb_open may solve the problem. Since my efforts where made in the context of a prove of concept I'll not further investigate the issue (at least in the near future). I'll eventually post an update at some later instance.