3 May
2012
3 May
'12
6:43 p.m.
OToby Thain wrote:
Because it's clearly simpler to have a single bus
USB isn't a bus, it's a tree-topology network. Even if it was a bus,
almost all PCs made in the last five years or more actually have more
than one, rather than a single bus.
and lose the specialised connectors.
USB uses specialized connectors. They were invented specifically for
USB, and aren't used for anything else. (Or at least, they aren't
*supposed* to be used for anything else.) PS/2 actually used connectors
that were standardized well prior to their PS/2 adoption. So what
actually happened was that we moved from common connectors for PS/2 to
specialized connectors for USB.
Despite that, the use of specialized connectors for USB is probably a
win, as it somewhat reduces the incidence of clueless people plugging
things into the wrong connectors.
However, the original USB connectors were IMHO very poorly engineered.
It appears to me that they were designed by people who were not
experienced connector designers. I think the Mini and Micro connectors
are better engineered.
Additionally, isn't USB more electrically
forgiving than PS/2?
Yes, although there's not really any reason that a newer hot-pluggable
version of the AT/PS2 interface couldn't have been made. The connectors
would only have to have been changed slightly, and the incremental cost
would have been zero in the volumes that PCs are made.
In practice, it seems like PS/2 interfaces were hot-pluggable in most
cases. I've hot-plugged PS/2 devices many hundreds of times, with not a
single failure, though I fully recognized the possibility of failure (of
either the device or the PC), and was willing to deal with the
consequences. I never recommended the practice to anyone else, because
then it would have been my responsibility if they damages something by
doing so.
Eric