I'am using the AT91SAM9RL64 Eval Board. To get to know USB, I extended
the USB-Example "usb-device-core-project-1.4-at91sam9rl-ek" from the
I extended the configuration descriptor with two endpoint descriptors,
one bulk in- EP (1) and one bulk out EP (6). The size of the endpoints
is 512 byte. DMA is activated.
For testing I call the USBD_Write- function with the following
Directly after this, my Callback- function is executed, because an
interrupt is triggered by the DMA Channel1, but I didn't read Data by
In my opinion this interrupt should only be triggert, when the host
read's data. Do you know a possible reason for this behavior? What I
have to consider?
On the host I use the LibUsb-Win32 driver/library.