titus-larsen-titus-1981-apple-interfacing

80 FOR P = 1 TO 10
90 GET A$
100 PRINT A(P): POKE 49318,A(P)
110 NEXT P
120 PRINT "END OF RUN": END
In this program, you must press the RETURN key to cause
computer to acquire a value. When the computer prints "ST A
DISPLAY ..." on the screen, it will display a value that it has sto
each time you press RETURN. The value will also be displayed
the LEDs in binary form. Note that a GET A$ command has
used here, instead of an INPUT A$. Is there any difference
Yes, the GET A$ command suppresses the question mark (), a
any character key (A, &, 1, etc.) may be used in place of the R
TURN key. The alphanumeric symbol is not displayed. This "cle
up" the display of the data values.
Ste§> 3
Run either your program, or ours, to acquire 10 data values. On
the values have been acquired, use the computer to display tn1rn,,F
What results do you observe
You should find that your values have been stored properly,
that they are also displayed and printed on the video monitor. If
do not require the values at the output port, could you modify
program so that it only displays the values on the monitor
Yes. Simply change line 100 to:
100 PRINT A(P)
and. remove line 90.
Step 4
The low-resolution graphics mode on the Apple could also
used to display the values in graphical form. We suggest that
attempt to use the HLIN command to draw a horizontal set of
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