Table of Contents
Advertisement
Interrupting Your Program
175
Pausing for Input
When the calculator executes a
instruction, program control
actually returns to the keyboard for the period of time (about one
second) of the pause. You can use a
to key data into or
perform functions from the keyboard, instead of using the
instruction to stop the running program completely. (Control does
not return to the keyboard during an
pause, however.)
When you press any key during the one-second ''window'" while the
calculator is executing a
instruction, that key actually
operates, and you have an additional one second of time to view the
result or to press another key. If you press yet another key during
the subsequent one second, the calculator will perform that operation
and pause for another second.
If you press a function key during a pause, the function key operates
upon the number contained in the X-register at the time. The result
of the function is then seen in the display for about one second.
Any function key that is programmable can also be operated from the
keyboard during a [(PAUSE .
If you press a digit key, or a series of digit keys, during a pause,
the number appears in the display for the length of a pause (about
one second) after you key in the number. (If a number has been input
from the program immediately before the pause, that number is first
terminated by the
instruction.) The number that you key in is
terminated at the end of the pause. Any subsequent digits in a program
will then be part of a new number.
When a
instruction has completed execution, the program
continues to be executed sequentially. If you have performed a
function, or keyed in a number, program execution begins with the
next instruction using the number that is in the displayed X-register
at the end of the pause. (You can also read a magnetic card during
a(PAUSE ) . More aboutthis in section 14, Card Reader Operations.)
Number termination occurs at the end of each (PAUSE ] , so you should
not attempt to key in a number during more than one subsequent
pause. Since you have about one second after your last keystroke
to continue keying in digits or functions, you don't need more than
one
instruction to key in even a very long number.
Advertisement
Table of Contents
