>                                                                      There
> are many devices that use an up/down mechanism for setting parameters or
> a round-robbin menu system in which one must keep pressing a selection button
> until the desired selection appears.  These mechanisms are pure Hell for
> users of the devices who happen to be blind.  Since thermostats, timers,
> and countless other control systems exist in homes and businesses, there
> is no telling when this problem will occur.  My suggestion is to have an
> abnormal key sequence such as the simultaneous pressing of both the up and
> down button or some other sequence to start the selection process at a
> known point in the circle.  This might be accompanied by a beep or some
> audible indication, if there is a sounder, but this feature would be very
> cheap to implement and would allow a blind person to use the device by
 learning
> the order of selections.

I would second this point.  Even for people with 20/20 vision, it's often
nicer to be able to operate devices by feel than looking at them.  I person-
ally prefer a slightly different tack though, on devices with numeric key-
pads but small displays: precede each menu choice on the display by a number
and then allow the user to *either* use arrow keys plus enter (if they do not
know what they want) or else use the numeric keys directly (if they do).  Of
course, it should go without saying that the numeric keypad should be design-
ed to be navigable by feel (none of those infernal flat mylar things!)  But
if the keyboard and display are both used to best advantage, it should be
possible to design an interface which is useful for both blind and sighted
people alike.

[BTW, beepers can be wonderful too.  While I think IBM's ProPrinter button
interface (which relies on beeps, since there's no display) is a bit of a
pain, the beeper is a considerable improvement over having nothing.  In
addition, it actually cost nothing in the ProPrinter since the "beeps" were
(from what I read) actually generated by giving short pulses to the print
head (too short to make it strike paper)!