Hello
I am going to implement a USB Device using LPC1768 and I need the isochronous transfer type for my application. To this purpose I studied the keil's USBAudio example. It is written in the datasheet of the MCU that the frame interrupt is generated every 1 ms, but this interrupt occurs very much more than one time in 1 ms in USBAudio. Where am I wrong?
> but the frequency of the generated wave is high (order of hunderd KHz).
Sound like the FRAME interrupt flag is not cleared by the stack.
Add this line to your USB_SOF_Event()
LPC_USB->USBDevIntClr = FRAME_INT; // clear FRAME interrupt flag
Tsuneo
The problem is solved. I appreciate your help.