I have an application when we stream sampled audio through the USB port on our K66 board. We sample audio at 16Khz, 16bit, 2 channels.
The USB0 port of the K66 MCU has a limited USB buffer size of 64 bytes which just fits our needs. In fact each 1ms 64 bytes can be transferred, which in turns equals to 2 channels * 2 bytes * 16 samples.
The problem is that from time to time we lose some samples as the sampling frequency is not 100% the same as the USB polling interval frequency and thus some samples are accumulating.
How to solve this ? In other words I need to send more than 64bytes per 1ms ISO frame. Any ideas ?