titus-larsen-titus-1981-apple-interfacing

Step 4
Determine the lamp patterns that will be required for norma
traffic light operation. How many are used What are they How ca
they be stored in the computer
There are only four patterns. They are (a) red on Elm, green o
Main ( 222) , ( b) red on Elm, yellow on Main ( 238) , ( c ) green on
Elm, red on Main ( 243) , and ( d) yellow on Elm, red on Main ( 245).
The values could be stored through the use of DAT A statements,
subscripted variables, or just as variables, one per lamp pattern.
Step 5
In the remainder of this experiment, we will assume a "yellow
period" of two seconds. Thus, if Elm Street is on a 10-second period,
the green light will be on for 10 seconds, followed by a 2-second
yellow, before the signal goes to red.
Write a program that will allow you to sequence through the.
light patterns, with a 6-second period on Elm and a 10-second period
on Main Street.
We used the following program:
10 M = 10: E = 6: P = 49318
20 DAT A 222, 238, 243, 245
30 READ L
40 POKE P,L
50 FO R R = l TO M
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