Objective Development Forums

I have some problem with your AVR USB driver on an AVRMEGA64 MCU. The problem is, when I Change default USB bus (PORTB PB0,PB1) to any other Ports like PORTC, the device will not be recognised by Windows. I have to say that, I Changed #defines in USBconfig.h already. But it seems the compiled driver pays no attention to these OR PORTB is the only choice for usb bus...

The Questions are :
1. IS THIS DRIVER WORKS ONLY WITH PORTB ON MCUs???
2. HOW TO CHANGE USB BUS TO OTHER PORTS WITHOUT PROBLEM??

You may use ANY port, provided that USB D+ and D- are both on the same port AND D+ is also wired to hardware interrupt 0 (INT0).

When you change usbconfig.h (or the Makefile or any other header file), do a "make clean" to ensure that all modules are compiled. Our Makefile does not contain dependencies for header files or the makefile itself.

I chang PORTB to PORTC in usbconfig and do all you say but it dosent work , please tell me what i must to do ?

The most likely cause is that your firmware does not initialize the ports correctly. Maybe it configures pull-up resistors for D+ and D- or configures these pins as output...