Find the HP calc which has the highest % of 1-function keys !


There may be more than 1 answer but the HP-70 is 100% 1 function keys, isn't it?


So is the HP-35, although one might object that the [arc] key gives [sin], [cos] and [tan] two functions apiece.



It depends on the point of view.

An IBM host is event driven where you may write several commands on a command line (or in a fullscreen application at several places) and only if you press ENTER (or a PF or PA key) the CPU starts working. Every calculator I know (HP-41) is a "key-per-function" machine where for every key hit the CPU clock starts. AFAIK this even holds true for a PC.

From the point of view for a normal user who interacts with a command line system like DOS (or a HP-71B) this looks like an event driven OS. But if you install on DOS some typing aids (like QuickLX from you will easily see that a HP200LX is a "key-per-funktion" from some point of view.


PS: was this the expected answer to your challenge?


Not really. The question was 1-Function per key.

"key-per-function" is not the same as "1-function per key"
All calculators can be called "key-per-function but not all calculators can be called 1-function per key.

Context comes into play.

A key per function means that everytime you hit a key "some function is executed." That function does not have to be the same, to be called a "key-per-function." Context may be important. The function executed, may depend on what was pressed prior to the key being pressed.

Both the HP-67 and the HP-70 can be called "key-per-function." You press a key and something happens.

Ex: SIN executes the function to display a '4' on the HP-67 but if the 'f' is pressed first, a sine function is executed. Context may matter and still be a "key-per-function" machine.

In the question asked, only 1-functions per key was the topic. Context does not matter. No matter when you hit the key only 1-funcction is executed.

A 1-function per key means that everytime you hit the key, "the same function" is executed. Context is not important. It does not matter what occurred prior to touching the key.


But if I hit SIN it depends on the contents of the X-register what happens. ;-)



Sorry, but we are speaking of function, not answer:-) The same functions is executed.

However, I was prepared for a different response from you:-) I figured you'd come back with, "depends on whether you are in radians or degree mode."

I would have responded, "no trig functions on an HP-70"

It's been a fun discussion, though.



I dont have one to check...
How about the HP10 adding machine?



Oh yes, I forgot RAD/GRAD/DEG. What I had in mind was, that depending on the contents of the X register SIN is calculated in a different manner. In other words if you hit the key a different branch in firmware is executed. This is easily seen on early HP-35 or HP-41 with a bug.

Of cause, for the end user it is allways SIN what is executed, but from my point of view: with a different function (started with the same key).

Ey! How you remarked that my appends are not to be taken too serious?


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