On Sat, Jan 29, 2011 at 2:52 AM, YES NOPE9 wrote: > I want to use the lowest end PIC that has a USB interface and > firmware to support the serial port class. =A0( Suggestions of micros > from other vendors such as NXP, TI, etc. are acceptable. ) > My intention is to have a small PCB that looks like a USB virtual > serial port and has a small amount of coding space left to do > something with the serial data flowing back and forth. =A0USB 1.1 > is okay since my data rate can be as low as 9600 baud. If your main audience is Windows users and you want to use the CDC-ACM class for the virtual serial port, I think potentially you are asking for trouble in the long run. Microsoft's usbser.sys is known to be buggy and can be a liability in the long run. Read this thread to see if HID is better suit for you. http://www.cygnal.org/ubb/Forum9/HTML/001227.html Some culprits of usbser.sys: http://www.microchip.com/forums/m538194.aspx http://www.cygnal.org/ubb/Forum9/HTML/000945.html The one in Win7 is supposed to better but again it has some problems. http://www.microchip.com/forums/m548293.aspx --=20 Xiaofan --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .