PWM stands for Pulse Width Modulation. While this is a good technical term, what it really means to us is this: with the PWM modification done to the controller board, software can now control the laser out power from 0% to 100%. This opens up a lot of new capabilities as well as providing for higher quality output for parts.Instructions For How To Do The PWM Modification
Carefully remove the Nano microprocessor from the controller board. Pay attention to orientation!
Move the jumper pin over to the other side.
Attached is a close up picture of the controller board, showing the jumper pin as it comes from the factory. Note the Nano microprocessor has already been removed.
The next attachment shows the PWM Mod done. The jumper has been moved over by one pin. Simple. Easy.
Replace the Nano microprocessor. Look carefully at the third picture attachment. Make sure you insert the Nano pins/legs into the correct socket holes. Depending on your controller board, the end of the controller board, the open circuit board hole in the Nano itself, may come down onto the first socket hole. The first Nano pin comes down into the second socket.
That's it for PWM Mod itself!
Next up, you'll have to install (flash) new firmware into the Nano microprocessor. The firmware that is there now, comes from the factory and it doesn't support PWM. So once you do the PWM Mod, the factory firmware (the Grbl .hex file) will no longer work*. In other words, you cannot use the factory Benbox software any more.How To Flash New Grbl Software Into The Nano
BenCutLaser currently uses Grbl version 0.9i or 0.9j .hex file and has built-in flashing capability. My Youtube Channel, located herehttps://www.youtube.com/user/rfresh1011
The video shows how to use BenCutLaser to flash Grbl software to the Nano microprocessor. While there are other external ways to do this, I wanted to make it easy on users of BenCutLaser, so I built-in the capability to do flashing.
Here is a link on my laser support forum with the exact steps on how to use BCL to flash a new firmware:http://benboxlaser.us/index.php/topic,657.0.html