alexz said:
I am developing a USB Mass Storage Device using the USBN9603 and PIC.
I have a question regarding the USBN9603.
What should I do exactly when I receive a zero length packet from the host?
Should I read again the status register or not?
Yes, you should. The very fact that you asked this question is probably because you've seen something regarding it in the datasheet but are not sure about it. If you don't do so, the RX_LAST bit would not be cleared and the interrupt would be retriggered.