Thanks for the info. I don't have 16u2 based Arduino for programming, just for USB to serial on Arduino boards. The first set of numbers will be used to finalize my design.
6v6gt:
Incidentally, I have also recently joined the ranks of those who have created a custom programmer. You might find something of use to you here: Multiprog v1.0 - Combined HighVoltage + ISP + USBTTL adapter/programmer - Exhibition / Gallery - Arduino Forum
I'll keep this in mind if I ever needed high voltage programming. Right now I have ATTiny 44/84 and ATTiny 45/85 shield (no LEDs as they are tiny board) and am currently doing 324/644/1284 which is a huge chip requiring bigger PCB so I ended up with extra space that I could slip in a few LEDs for status. Is this the biggest DIP chip of all AVR chip? ATMega2560 does not come in DIP AFAIK.