diff --git a/src/main.cpp b/src/main.cpp
index 48df919..6273a2f 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,25 +1,48 @@
 #include "Arduino.h"
 
-// Set LED_BUILTIN if it is not defined by Arduino framework
-// #define LED_BUILTIN 13
+#define DIR_PIN 2
+#define STEP_PIN 3
+#define STEPS_PER_REV 200
 
 void setup()
 {
-  // initialize LED digital pin as an output.
   pinMode(LED_BUILTIN, OUTPUT);
+  pinMode(STEP_PIN, OUTPUT);
+  pinMode(DIR_PIN, OUTPUT);
 }
 
+int pinState = LOW;
+int speedDelay = 50;
+int speedDelayDir = +1;
+
 void loop()
 {
-  // turn the LED on (HIGH is the voltage level)
-  digitalWrite(LED_BUILTIN, HIGH);
+  digitalWrite(DIR_PIN, LOW);
+  for (int i = 0; i < STEPS_PER_REV; i++)
+  {
+    digitalWrite(STEP_PIN, HIGH);
+    delayMicroseconds(500);
+    digitalWrite(STEP_PIN, LOW);
+    delayMicroseconds(500);
 
-  // wait for a second
-  delay(1000);
+    delayMicroseconds(speedDelay);
 
-  // turn the LED off by making the voltage LOW
-  digitalWrite(LED_BUILTIN, LOW);
+    if (speedDelay > 5000){
+      speedDelayDir = -1;
+    } else if (speedDelay < 50){
+      speedDelayDir = +1;
+    }
 
-   // wait for a second
-  delay(1000);
+    if (speedDelayDir == +1) {
+      speedDelay += 50;
+    } else {
+      speedDelay -= 50;
+    }
+
+  }
+
+  pinState = !pinState;
+  digitalWrite(LED_BUILTIN, pinState);
+
+  // delay(500);
 }