Step 2: Controlling the Speed of a Stepper Motor

Step 2: Controlling the Speed of a Stepper Motor Hello everyone. This is Eric Park, 3D Printer Engineer from South Korea. Welcome back to the series. Quick recap from Step 1: We set up the GPIO pins on the Raspberry Pi We connected the A4988 driver to a NEMA17 motor We sent 200 pulses to the motor and watched it complete one full revolution for the first time That first spin felt surprisingly satisfying. But the motor was just running at one fixed speed. Step 2 is about changing that. What Controls Speed? In Step 1, the code looked something like this: for ( int i = 0 ; i < 200 ; i ++ ) { digitalWrite ( STEP_PIN , HIGH ); delay ( 2 ); digitalWrite ( STEP_PIN , LOW ); delay ( 2 ); } The delay(2) is a 2 millisecond pause after each pulse. The motor waits for that pause before receiving the next pulse. So the relationship is simple: shorter delay = less waiting = faster motor longer delay = more waiting = slower motor That is the entire idea behind Step 2. We are not changing anything com