SunFounder R3, Руководство пользователя

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SunFounder uno-and-mega-kit
for (initialization; condition; increment) { //statement(s); }: The for statement is used to repeat a block of statements
enclosed in curly braces.The initialization happens first and exactly once. Each time through the loop, the condition
is tested; if it’s true, the statement block, and the
increment
is executed, then the
condition
is tested again. When the
condition
becomes false, the loop ends.
Set flowing led lights
Use the for() statement to set pin2-pin9 to a high level inturn.
for ( int a = 2 ; a <= 9 ; a ++ )
{
digitalWrite (a, HIGH ); //turn this led on
delay ( 100 ); //wait for 100 ms
}
Then let the 8 LEDs go out from pin9 to pin2 in turn.
for ( int a = 9 ; a <= 2 ; a -- )
{
digitalWrite (a, LOW ); //turn this led on
delay ( 100 ); //wait for 100 ms
}
Finally, use the same way to turn on the 8 LEDs from pin9 to pin2 in turn and let them go out in turn.
for ( int a = 9 ; a <= 2 ; a -- )
{
digitalWrite (a, HIGH ); //turn this led on
delay ( 100 ); //wait for 100 ms
}
for ( int a = 2 ; a <= 9 ; a ++ )
{
digitalWrite (a, LOW ); //turn this led on
delay ( 100 ); //wait for 100 ms
}
Experiment Summary
Through this experiment, you have learned how to use for() statement which is a very useful statement when you want
to short the code.
88 Chapter 6. For Mega2560 User