Make a Fan Controller with Arduino

1#include <EEPROM.h>
2
3#define FAN_PIN 3;
4#define FS_ADDR 0x01
5int   fanSpeed;
6
7void setup() {
8  // put your setup code here, to run once:
9   pinMode(3, OUTPUT);
10  EEPROM.get(FS_ADDR, fanSpeed);
11  if(fanSpeed < 1)   fanSpeed = 255;
12  analogWrite(FAN_PIN, fanSpeed);
13  Serial.begin(9600);
14
15}
16char   rx_byte = 0;
17String input = "";
18
19void loop() {
20  if (Serial.available()   > 0) {    // is a character available?
21    rx_byte = Serial.read();       //   get the character
22  
23    // check if a number was received
24    if ((rx_byte   >= '0') && (rx_byte <= '9')) {
25      input.concat(rx_byte);
26      
27    }
28     else if (rx_byte == '\
29') {
30      Serial.print("Received: ");
31      Serial.println(input);
32       if(input.toInt() < 256) {
33        fanSpeed = input.toInt();
34        EEPROM.put(FS_ADDR,   fanSpeed);
35      } else {
36        Serial.println("Invalid Number");
37       }
38      input = "";
39    }
40    else {
41      Serial.println("Not   a number.");
42    }
43  } // end: if (Serial.available() > 0)
44  analogWrite(FAN_PIN,   fanSpeed);
45}

1#include <EEPROM.h>
2
3#define FAN_PIN 3;
4#define FS_ADDR 0x01
5int  fanSpeed;
6
7void setup() {
8  // put your setup code here, to run once:
9  pinMode(3, OUTPUT);
10  EEPROM.get(FS_ADDR, fanSpeed);
11  if(fanSpeed < 1)  fanSpeed = 255;
12  analogWrite(FAN_PIN, fanSpeed);
13  Serial.begin(9600);
14
15}
16char  rx_byte = 0;
17String input = "";
18
19void loop() {
20  if (Serial.available()  > 0) {    // is a character available?
21    rx_byte = Serial.read();       //  get the character
22  
23    // check if a number was received
24    if ((rx_byte  >= '0') && (rx_byte <= '9')) {
25      input.concat(rx_byte);
26      
27    }
28    else if (rx_byte == '\n') {
29      Serial.print("Received: ");
30      Serial.println(input);
31      if(input.toInt() < 256) {
32        fanSpeed = input.toInt();
33        EEPROM.put(FS_ADDR,  fanSpeed);
34      } else {
35        Serial.println("Invalid Number");
36      }
37      input = "";
38    }
39    else {
40      Serial.println("Not  a number.");
41    }
42  } // end: if (Serial.available() > 0)
43  analogWrite(FAN_PIN,  fanSpeed);
44}