LPC11U35FHI33/501 USB HID ROM API NAK Issue

[BBQ]

I am working on LPC11U35FHI33/501 as USB HID device using ROM API(USB on-chip driver).

< Issue >
HID Device send NAK to USB host when USB host send OUT transaction (Interrupt out) to device.
At first, ACK is returned normally, but at a certain point it becomes NAK, and after that NAK is returned always.

< Question >
What are the conditions under which a device returns a NAK?

[Alice_Yang]

Hello @BBQ 

Recommend you check the application code in USB device. This is depends on device application code.

BR

Alice