Laser intensity control - RAMPS 1.4 and TTL (5V) diode laser how to
I am new to this forum and would like to start new discussion about TTL laser control and installation of TTL laser with Repetier firmware. I have intent to install laser on a 3D printer and I have gone through number of forums and discussions in order to get ready for this installation. Unfortunately, I realized that there is no plain explanation on what is the best method of connecting TTL controlled diode laser to a RAMPS 1.4 board with Repetier firmware. I would like to focus the discussion on engraver with Arduino Mega board with 1.4 RAMPS board and Repetier firmware. The laser I have is 15W diode laser with 5V TTL control and standalone power supply.
Here is summary of what I learned and possible options/solutions:
Here is the link to a step by step guide on how to use laser with Marlin firmware and RAMPS 1.4 https://www.vicious1.com/wp-content/uploads/2016/01/MPCNC-laser-add-on-walk-through.pdf Very simple to follow and an excellent guide. The key point here is to remap fan output D9 (12V) to pin 44 (5V) and then use fan speed control to control laser intensity. Using the analogy from Marlin the same could be done in the Repetier firmware. Open pins.h file find where fan pin is assigned and change it from 9 to 44. Save the file and reload to Arduino. Connect Laser TTL to pin 44. Please note that I have not tried this method and I don't know if this would work (getting ready to test in few weeks). If someone has tried this with Repetier firmware and RAMPS 1.4 please share your experience within this forum. It seems that this is not recommended solution from Repetier but sounds attractive to me.
In Repetier firmware Laser mode can be enabled in the configuration process. What I hear and read is that Repeitier firmware will provide only ON and OFF laser control by using this method (correct me if I am wrong).This would not satisfy my expectations for laser control.
This is something that "Repetier" is recommending as a solution for laser intensity control. This solution requires creation of something what is called custom extensions and custom events. Although, it sounds simple it may be difficult option for us who are not good in programming and code editing. I have not found any complete step by step guide on how this code can be changed and implemented. From my point of view this is the best option to control laser intensity with Repetier firmware but…… I don't know how to edit the code. Does anyone out there has the link or can provide how to guide for laser intensity control within Repetier firmware.
Regards and thank you in advance