SunFounder R3, Руководство пользователя

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SunFounder uno-and-mega-kit
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int sensorValue = 0 ; // value read from the sensor
int ledLevel = 0 ; // sensor value converted into LED 'bars'
The 8 LEDs are connected to pin5-pin12, in this code, use a array to store the pins, ledPins[0] is equal to 5, ledPins[1]
to 6 and so on.
Set 8 pins to OUTPUT
for ( int led = 0 ; led < NbrLEDs; led ++ )
{
pinMode (ledPins[led], OUTPUT ); // make all the LED pins outputs
}
Using the for() statement set the 8 pins to OUTPUT. The variable led is added from 0 to 8, and the pinMode() function
sets pin5 to pin12 to OUTPUT in turn.
Read the analog value of the photoresistor
sensorValue = analogRead (photocellPin); // read the value of A0
Read the analog value of the photocellPin(A0 ) and store to the variable sensorValue.
analogRead(): Reads the value from the specified analog pin. Arduino boards contain a multichannel, 10-bit analog
to digital converter. This means that it will map input voltages between 0 and the operating voltage(5V or 3.3V) into
integer values between 0 and 1023.
Serial . print ( "SensorValue: " );
Serial . println (sensorValue); // Print the analog value of the photoresistor
Use the Serial.print()function to print the analog value of the photoresistor. You can see them on the Serial Monitor.
Serial.print(): Prints data to the serial port as human-readable ASCII text. This command can take many forms.
Numbers are printed using an ASCII character for each digit. Floats are similarly printed as ASCII digits, defaulting
to two decimal places. Bytes are sent as a single character. Characters and strings are sent as is.
Serial.println(): Thiscommand takes the same forms as Serial.print(), but it is followed by a carriage return character
(ASCII 13, or ‘r’) and a newline character (ASCII 10, or ‘n’).
Map the analog value to 8 LEDs
ledLevel = map (sensorValue, 0 , 1023 , 0 , NbrLEDs); // map to the number of LEDs
Serial . print ( "ledLevel: " );
Serial . println (ledLevel);
The map() command is used to map 0-1023 to 0-NbrLEDs(8), (1023-0)/(8-0)=127.875
0-12
7.875 128-2
55.75 2 56-38
3.625
384-
511.5 5 12-63
9.375
640-7
67.25 7 68-89
5.125
896
-1023
0 1 2 3 4 5 6 7
If sensorValue is 560, then the ledLevel is 4.
7.9. Lesson 9 Photo resistor 263