这是Arduino 控制LED灯的代码，请问这段代码什么意思？

const int ledPin = 3; // the number of the LED pin

void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
pinMode(ledPin, OUTPUT);
//digitalWrite(ledPin, LOW);
}
char i = 255;
int sensorValue = 0;
unsigned char aa,bb;
void loop() {
// put your main code here, to run repeatedly:
if (Serial.available() > 0)
{
unsigned char a = Serial.read();
if(a == 170)
{
delay(10);
aa = Serial.read();
delay(10);
bb = Serial.read();
}
}
sensorValue = analogRead(A0);
sensorValue = 1024 - sensorValue ;
sensorValue = sensorValue * 0.25;
if(aa == 0x01)
{
analogWrite(ledPin,sensorValue);
}
else
{
analogWrite(ledPin,255-bb);
}
Serial.write(0xaa);
Serial.write(0x01);
Serial.write(0x01);
Serial.write(sensorValue&0xff);
delay(100);
}

哪句话不懂？

unsigned int aaa[14][12]= { {1,1,1,1,1,1,1,1,1,1,1,1}, {0,0,0,0,0,0,0,0,0,0,0,0}, {1,1,1,1,1,1,1,1,1,1,1,1}, {0,0,0,0,0,0,0,0,0,0,0,0}, {1,1,1,1,1,1,1,1,1,1,1,1}, {0,0,0,0,0,0,0,0,0,0,0,0}, {1,1,1,1,1,1,1,1,1,1,1,1}, {0,0,0,0,0,0,0,0,0,0,0,0}, {1,1,1,1,1,1,1,1,1,1,1,1}, {0,0,0,0,0,0,0,0,0,0,0,0}, {1,1,1,1,1,1,1,1,1,1,1,1}, {0,0,0,0,0,0,0,0,0,0,0,0}, {1,1,1,1,1,1,1,1,1,1,1,1}, {0,0,0,0,0,0,0,0,0,0,0,0}, }; int i = 0; int j = 0; void setup() { serial.begin(9600); // set up serial at 9600 bps pinmode(2, output); // d2-d13 各接1个led pinmode(3, output); pinmode(4, output); pinmode(5, output); pinmode(6, output); pinmode(7, output); pinmode(8, output); pinmode(9, output); pinmode(10, output); pinmode(11, output); pinmode(12, output); pinmode(13, output); } void loop() { for(i=0;i<14;i++) // 数组 行,超过14行重置 { for(j=0;j<12;j++) // 数组 列 { digitalwrite(j+2, aaa[i][j]); // 数组 0,0 开始 } delay(1000); } }