|Re: Reminds me...|
Message #10 Posted by Vieira, Luiz C. (Brazil) on 14 Jan 2010, 5:52 p.m.,
in response to message #9 by Garth Wilson
Ángel´s first 4K 41Z had a programmable, complex-addressed USER keyboard through a single MCODE function. Anyway, any pair of consecutive USER assignment (or after packing the existing ones) will ocupy a main RAM register, as we know.
For me, the best cost-benefit relation is the use of sofkeys (HP19, HP28, HP42S, HP48-series and so), and in some applications, like the ones in the HP41 Advantage Pack, such feature is simulated (not the softkeys themselves, something close to). The HP32S also takes advantage of the ALPHA keyboard with the addition of the small arrows pointing to the active keys.
The main issue of the USER keyboard is to remember what is assigned to which key, and I believe the [NULL] feature in the HP41 was one of the solutions to help the user to 'check before using' a particular key in user mode. If we have a set of USER keyboards, I guess the user would have to retain more information, though.
Please, these are just my own considerations about the subject. I neither have an answer, nor a solution to propose, but I really would like to have another possibility for the multiple user defined keyboards.