Thinking of keyboard interfaces (HP9915)

For ordinary typing, ie, using a keyboard as a text input device, I suspect you are correct. But when using a keyboard as a multi-button input device that happens to have lots of buttons, which (for example) many games do, it's far less clear. It would not surprise me to see rollover requirements go as high as nine or maybe even ten in extreme cases; certainly when playing the piano I need N-key rollover for N above 6 - fortunately my piano, unlike most computer text keyboards, is designed for that sort of thing. (It's an electronic piano, not a mechanical one, but a pretty good one as such things went when I bought it; it definitely supports N-key rollover for N well over 6.) /~\ The ASCII Mouse \ / Ribbon Campaign X Against HTML mouse at rodents-montreal.org / \ Email! 7D C8 61 52 5D E7 2D 39 4E F1 31 3E E8 B3 27 4B