Made a simple Arduino program, want to know how to make it cleaner/smaller

Question

Here is my code. It compiles and runs on my Arduino MEGA 2560.

#include "Arduino.h"//Standard Arduino Library
#include "Print.h" //Print to serial library, Serial.Println would not work by default for some reason.
#define led_pin 13 //Set var led_pin to equal 13, meaning pin 13
#define pinstate digitalRead(read_pin)
#define read_pin 50 // " 50, "50
int loopstore; //Def as global var so it won't be reset on next loop iteration

void setup() //Setup function, used to set pins and vars before running main Arduino Program
{


Serial.begin(9600); //Start serial comms, set baud rate

Serial.println("\nHello User.\n\nArduio has set baud rate and started serial communication.\n\nThank You, Sketch will run momentarily.\n\n");

pinMode(led_pin,OUTPUT); //Set led_pin to digital output mode;

pinMode(read_pin,INPUT); //", " read mode
}


void loop() //Actual program

{
loopstart = 1;
do
{
++loopstore;
} while (loopstart == 0);

Serial.println("This program has ran this many times:\n");

Serial.println(loopstore);

digitalWrite(led_pin,HIGH); //Set pin high
delay(1000); //Wait

if (pinstate == 1) //If else statement for outputting pin state to console
{
    Serial.println("\nPin is in a HIGH state\n\n"); // Output to console
}
else
{
    Serial.println("Pin is in a LOW state\n\n"); // Output to console
}

delay(1500); //Wait

digitalWrite(led_pin,LOW); //Set pin to Low State
delay(1000); //Wait

if (pinstate == 1) //If else funct for outputting pin state to console
{
    Serial.println("Pin is in a HIGH state\n\n"); // Output to console
}
else
{
    Serial.println("Pin is in a LOW state\n\n"); // Output to console
}

delay(1000); //Wait

digitalWrite(led_pin,HIGH); //Set pin high
delay(1500); //Wait

if (pinstate == 1) //If else funct for outputting pin state to console
{
    Serial.println("Pin is in a HIGH state\n\n"); // Output to console
}
else
{
    Serial.println("Pin is in a LOW state\n\n"); // Output to console
}

delay(1000); //Wait

digitalWrite(led_pin,LOW); //Set pin to Low State
delay(1500); //Wait

if (pinstate == 1) //If else funct for outputting pin state to console
{
    Serial.println("Pin is in a HIGH state\n\n"); // Output to console
}
else
{
    Serial.println("Pin is in a LOW state\n\n"); // Output to console
}

delay(1000); //Wait

digitalWrite(led_pin,HIGH); //Set pin high
delay(500); //Wait

if (pinstate == 1) //If else funct for outputting pin state to console
{
    Serial.println("Pin is in a HIGH state\n\n"); // Output to console
}
else
{
    Serial.println("Pin is in a LOW state\n\n"); // Output to console
}

delay(1000); //Wait

digitalWrite(led_pin,LOW); //Set pin to Low State
delay(500); //Wait

if (pinstate == 1) //If else funct for outputting pin state to console
{
    Serial.println("Pin is in a HIGH state\n\n"); // Output to console
}
else
{
    Serial.println("Pin is in a LOW state\n\n"); // Output to console
}
}

I'm just learning to work with Arduino and I made a quick and dirty program that simply sets the pin state of the LED pin on the Arduino (13) and then reads it with pin 50. It's a pointless program but I'm trying to learn/practice.

For extra practice I also made a counter for the amount of times the loop() function runs.

The "Do While" statement I made increments the counter. Then I print the result to serial afterwards. See that if loopstart == 0, the "Do While" statement runs again. This is impossible because it never gets set to 0. I wanted a sort of "passthrough" counter, but is this the best way?

I am almost positive there has to be a way to do what I did above more efficiently, but being new to Arduino (and programming in general), I have no idea how I would be able to simplify this.

Anybody have any suggestions or perhaps a place where they could point me to?

I've tried looking online for examples of a counter in C++, but I couldn't find anything that was outside of a "For" loop.

Thank you for your time and helping a kid learn!

Edit: Did not know about CodeReview. Thanks!

Answer 1

Maybe something like that can best suit you. If I understand correctly your program basically toggle 3 times the led and then check for the pin state with a delay before and after (which is variable).

If you want me to detail some more parts, ask me I will edit my post ;)

#include "Arduino.h"//Standard Arduino Library
#include "Print.h" //Print to serial library, Serial.Println would not work by default for some reason.

// Some debugging macros
#define DEBUG 1
#define slog(a) { if (DEBUG) Serial.println(a); }; // No debug directive will be in compiled file if DEBUG is set to 0

// Let's define our port mapping
#define LED_PIN _BV(7) //bit 7 on PORTB on 2560 correspond to digital pin 13 (check http://arduino.cc/en/Hacking/PinMapping2560)
#define READ_PIN _BV(3)

// Some quick access for led pin / read pin manipulation
// Let's use bitwise operation on PORTB, digitalRead => 28 cycle, direct read with PORTB => 1 cycle (28x faster!)
// I prefer defining setters as functions, easier to read, but you are not force to (it is exactly the same once compiled)
//#define LED_ON() { PORTB |= LED_PIN; } // Put LED_PIN bit to 1 on PORTB
//#define LED_OFF() { PORTB &= ~LED_PIN; } // Put LED_PIN bit to 0 on PORTB
#define LED_TOGGLE() { PORTB ^= LED_PIN; } // Put LED_PIN bit to 0 if it was 1 or to 1 if it was 0

#define READ_STATE PORTB & READ_PIN // Read LED_PIN bit on PORTB


int loopcount = 0; //Def as global var so it won't be reset on next loop iteration

// Let's create an array which will define all the delays before and after serial calls
// ex: {1000, 1500} => 1000ms before serial output, 1500ms after serial output
int wrapDelays[][2] = { {1000, 1500}, {1000, 1000}, {1500, 1000}, {1500, 1000}, {500, 1000}, {500, 0} };

void setup() //Setup function, used to set pins and vars before running main Arduino Program
{
    if (DEBUG) Serial.begin(9600); //Start serial comms, set baud rate
    slog("\nHello User.\n\nArduio has set baud rate and started serial communication.\n\nThank You, Sketch will run momentarily.\n\n");

    // Output/Input for PORTB (in DDRB register)
    DDRB |= LED_PIN; // Set LED_PIN to digital output mode (put LED_PIN bit to 1)
    DDRB &= ~READ_PIN; // Ensure READ_PIN is in input mode (put READ_PIN bit to 0)
}

// ToggleLed, write read pin state on serial, and wait `delayBefore`ms before and `delayAfter`ms after
void toggleLedBetweenDelays(int delayBefore, int delayAfter){
    LED_TOGGLE();

    if (delayBefore > 0) delay(delayBefore);

    if (READ_STATE) {//If else funct for outputting pin state to console
        slog("Pin is in a HIGH state\n\n"); // Output to console
    }
    else
        slog("Pin is in a LOW state\n\n"); // Output to console

    if (delayAfter > 0) delay(delayAfter);
}

void loopCounter(){
    loopcount++; // increase count of loops
    slog("This program has ran this many times:\n");
    slog(loopcount);
}

void loop() //Actual program
{
    for (int i = 0, l = sizeof(wrapDelays) / sizeof(wrapDelays[0]); i < l; ++i)
    {
        toggleLedBetweenDelays(wrapDelays[i][0], wrapDelays[i][1]);
    }

    loopCounter();
}

Note: Don't forget that it's not because the code you write is smaller that the final compiled binary will also be smaller/optimized.