On Fri, Mar 12, 2010 at 7:44 PM, Xiaofan Chen wrote: > On Sat, Mar 13, 2010 at 8:32 AM, Vitaliy wrote: >> Compared to FT232R: >> >> + $1.50 vs $2.85 in qty >> + 20 pins vs 28 >> + smaller package > > All not bad. > >> - Windows XP/Vista/7 drivers only > > The reason is that they use a HID+CDC USB composite device, > it will need Windows XP SP3 and Vista/Win7. > > The biggest negative is that Microchip is using the Windows > built-in usbser.sys driver which will cause many headaches > for Microchip. > > As of now, this chip is not recommended to be used from > my point of view. usbser.sys caused and is still causing > many problems even though it is getting slightly better > now. For hobbyists and small business, it might still be ok. > >> >> - Requires external 12Mhz crystal > > Microchip has not mastered the know-how to use internal > RC oscillator (plus sophisticated PLL) for full speed USB. > >> I'm sure the negatives are not a factor for many applications. > > The single negative of using usbser.sys render all the positives > useless. > > > -- > Xiaofan http://mcuee.blogspot.com I'll admit I'm not a USB guru but since it has configurable VID/PID, couldn't you write your own driver if you were serious about using it for one reason or another? -- Martin K. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist