Provide at least one mode that does not require a response time. Alternatively, a response time may be required if it can be by-passed or adjusted by the user over a wide range.
1. Many persons find it very difficult to operate
time-dependent controls.
2. Some strategies which address this problem include:
a.
Avoid any timed-out situations or
provide instances where the user must respond to a question or moving display in
a set amount of time or at a specific time (e.g., a rotating display).
b.
Where timed responses are required or appropriate, allow
the user to adjust them or set the amount of time allotted to complete a
given task. Warn users that time is
running out and allow them to secure
extended time.
c. If the standard mode of operation would be awkward or inefficient, then provide an alternate mode of operation that offers the same functions.
Note: Most portable products have some sort of timeout, if only for reasons of power conservation. Some telephone networks limit the number of rings before canceling the call. Voice mail systems are set to answer after a certain number of rings, which can be adjusted by the subscriber. However, there is usually a maximum of six rings, which may not be enough for some people. Aside from wireless telephones, products that use buffer dialing do not have short timeouts.
Some adjuncts (e.g. amplifiers)
Modems.(software interface for dialing or setting parameters)