Fiber Laser RS232 DB9

Hello smoothie builders…

I want to know if it’s possible to control a fiber laser from smoothieboard.
In the past, I was able to control a Huanyang VFD using RS-485 breakout with the use of pins rx (P2.6) and tx(P2.4)

Nowadays I want to know if there is a chance to control a fiber laser from smoothieboard using
a RS232 breakout with the same pins. The fiber laser that I want to control has a RS232 DB9 port,
and the specs says it’s possible to control this laser using rx and tx pins.
Is it possible ?

Reading the laser guide, I understand that I can’t see a config option to say “rs232” (like “modbus” for vfd control using rs-485 breakout). The laser guide is focused over co2 lasers…

Is there a workaround or only co2 lasers can be controlled using smoothie ?
I’m not an expert, I’m only looking for help and knowledge…
Any help would be appreciated…



RS-232 is a signalling level (RS-485) is the same. Modbus is a protocol that is common for running over RS-485. So I think your question is whether someone here would know what protocol is used for your particular fiber laser, and secondarily whether smoothie supports it.

I don’t know whether anyone here has that information but if they do it’s more likely that they will be able to help if you share what kind of fiber laser you have.

Thanks for the info !. In this case, the fiber laser could be something like this…
https://www.alibaba.com/product-detail/JPT-LPE-Series-MOPA-Fiber-Laser_1600185387964.html?spm=a2700.galleryofferlist.normal_offer.d_title.34ec63ae4H4Yk0

I know the laser guide does not cover something related with fiber lasers, but, I’m trying to figure out if it’s possible to control a fiber laser using one of the two ports that are available or even if there are fiber lasers that could work (wiring) like co2 lasers…

I don’t know what controller (smoothie) software is needed to drive a RS232 interface designed to drive a fiber laser via serial Rs232?

It may be easier to use the DB25 interface as it has discrete signal controls. Didn’t spend any time looking to see if the smoothie has enough programmable ports to drive it.

The biggest challenge it seems to me is what controller software is needed/available to create the needed fiber interface.

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Given the reference to a “red card” I wonder whether this PDF provides the protocol information:

It isn’t obvious to me that this protocol has been implemented in Smoothieware, but I could have easily missed it.

Thanks for your time and your support !

I don’t know how it’s possible to start. By the way, the docs of some fiber lasers say ‘db9 port (rs232)’ is only used for debugging purposes, and other says only ‘db25 port (parallel port)’ is going to be used to connect and send the values that you want. The attached doc says it’s possible to send commands using RS232 port. So… I would like to think (it’s only a thought) that it’s possible to control this kind of laser using some digital/pwm pins from the smoothieboard and activate them (like switch option controlled by gcode command) to say “I want to turn on/turn off the laser or I want certain percent of the beam”, but, maybe “an intermediate” between smoothieboard and the fiber laser source will be required to “catch” smoothieboard pin activations and send the desired meaning of that pins to db25 or db9 port to control the laser source. By the way, something “similar” could be done if an ethernet option is included with the fiber source and use something like “telnet” to send the commands or anything to accomplish the laser control.

If the first purpose is to use the db25 port (to control manually), some kind of program must be written to send the bit sequence or commands to finally control the laser fiber source.

I don’t know, I was wondering about that…

Again, I really appreciate your time and response…

I don’t think that smoothieware has a module that would support breaking out the power level into pins 1-8 which are clearly an 8-bit power level. I might be wrong, and when @Arthur_Wolf is around he can certainly say for sure.

I was curious so did some more surfing …

This doc shows more detailed specs for serial Rs232 and parallel DB25 interfaces that closely matches the connector assignments shown in the above DB25 definitions above.

It seems there is a lot of functional and control signal conversion needed between a CO2 style laser control and a fiber one.

Yeah, one of the problems I wasn’t thinking about for the parallel port DB-25 interface is that it’s specified at 5V TTL and the smoothieboard (as you would expect for a modern device) runs at 3.3V. So level shifters I guess?

4.4v in my tests using level shifter… I don’t know if this will be enough or a special breakout designed for that purpose could help…