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Open-source LPM project base. Your thoughts?

Trevor

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I recently wrote an Arduino project that is designed to be used as a standalone datalogger or as the core of an LPM. It's a pretty simple project designed to remove one of the barriers to entry of the hobbyist LPM market and help ease the process of getting into embedded programming.

I'd like to release it open-source. However, I'm not sure what license I want to use and I'd like community input. I was considering the MIT license and the GNU GPL.

The MIT license's key feature is that it gives complete permission to use the source code in a closed-source, commercial application.

The GNU GPL's key feature is that it requires that any derivative works also be open-source.

If people are actually interested in this, I plan on putting out more open-source stuff. Those will also go out under the license chosen here. I just want to make sure that whatever terms get put on the sources line up with the way we do things around here... and I could make a solid case both ways.

So, any thoughts on licensing? Or general thoughts?

-Trevor
 

Kmor2004

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I say just use the GNU, thats what most of open-source stuff uses, also you did figure in the Vref resolution with your code right?

Like if your powering it with 5V and left the Vref pin floating that each ADC count will be 5mV so if you have a count of 100 you are actually measuring 500-504mV, unless you used a smaller Vref voltage would would give you better results.
 

Trevor

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I've been working with Arduinos in the framework of LPM's for over a year now. :)

I have it written so that you configure which Vref setting to use (DEFAULT, INTERNAL, EXTERNAL, and the Mega-only options), and then also define the Vref as a double so as to clean up the code a little bit and make sure that someone who wants to use an external reference is also covered.

I was thinking GNU could be a good option for starting some sort of more open-source trend, but the MIT license would make this code function a lot like a tutorial here (in the sense that you can just take the resources and use them however you want).

-Trevor
 
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Wolfman29

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How can one use something for commercial purposes but still have it be open-source? That is a little bit contradictory, is it not?
 

Trevor

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Then yeah, I'd say include both.
How can one use something for commercial purposes but still have it be open-source? That is a little bit contradictory, is it not?
Yeah, not sure how I could include both. The open-source mandate in the GPL would override the MIT license.


I'm sort of leaning toward the MIT license honestly. While I'd like to see more open-source projects out there for us, I think I'm more interested in seeing more LPM's being built. :D

-Trevor
 
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Guyfromhe

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People use GNU stuff for commercial products all the time... Look at pretty much any router on the market... Their almost all running Linux.

Sounds like a cool idea... How would one calibrate a home built unit though.. or is this just meant to be a data logger for a LPM?
 

Trevor

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I would think the GNU would offer the chance to build more?
Well... with the MIT license someone wouldn't be legally required to release a source.

On the one hand, I think people would be more likely to enter the market with products based on my codebase if they knew they weren't required to release a source.

On the other hand, a free non-commercializable alternative to what's on the market now could be pretty cool to have around - especially if it was more than just me contributing. :)

EDIT: @Guyfromhe: Maybe I'm misunderstanding the license then. Do said routers have somewhere where you can acquire the source? If not, what version of GNU are they under? Regarding calibration, I know quite a good number of people here would be willing to help someone calibrate their LPM. :)

-Trevor
 
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jib77

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People use GNU stuff for commercial products all the time... Look at pretty much any router on the market... Their almost all running Linux.

Sounds like a cool idea... How would one calibrate a home built unit though.. or is this just meant to be a data logger for a LPM?
Although the router is running a distribution of linux (most likely uClinux under the LGPL) the applications written to run on the platform can stay closed source. The only thing you have to release source for is if you make any changes to linux, its libraries, or if you "pollute" your source with GPL'd source code.
 

Kmor2004

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To make you feel better trevor, I'm making a LPM Right now I just need to get a resonator (stupid 8MHz internal) then I'll start making posts with codes and pics (using a 328-pu with arduino bootloader on it).

In terms of calibrating I would think that if Trev made the code, and limited it to a specific Vref then the only real differences would be the Measuring device TEC, thermocouple, etc, then all trev would need to do is list the equivalant mV/mW and you could adjust it accordingly.
 

lasersbee

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On the other hand, a free non-commercializable alternative to what's on the market now could be pretty cool to have around - especially if it was more than just me contributing. :)
-Trevor
I may be missing something...:yabbem:
A non-comercialized alternative to what exactly...:thinking:


Jerry
 

Trevor

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I may be missing something...:yabbem:
A non-comercialized alternative to what exactly...:thinking:

Jerry
Well, the MIT license would allow someone to simply commercialize the project as-is, or modify it slightly and commercialize it. All without restriction.

The GNU license would allow someone to commercialize it, but if modified they would have to also release the source.

(Hope that explains the commercialization aspect.)

This whole project would be an inexpensive, high quality, open-source alternative to any LPM on the market - be it a Kenometer, Radiant Alpha, or LaserBee.

I've always thought having an open-source LPM platform out there would be cool. No one had made one, so here I am... :)

-Trevor
 

lasersbee

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Well, the MIT license would allow someone to simply commercialize the project as-is, or modify it slightly and commercialize it. All without restriction.

The GNU license would allow someone to commercialize it, but if modified they would have to also release the source.

(Hope that explains the commercialization aspect.)

This whole project would be an inexpensive, high quality, open-source alternative to any LPM on the market - be it a Kenometer, Radiant Alpha, or LaserBee.

I've always thought having an open-source LPM platform out there would be cool. No one had made one, so here I am...

-Trevor
If I understand correctly...

you want develop a FREE Laser Power Meter for the masses....:cool:

Am I correct in assuming that...:thinking:


Jerry
 
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Trevor

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If I understand correctly...

you want develop a FREE Laser Power Meter for the masses....:cool:

Am I correct in assuming that...:thinking:

Jerry
That and hopefully spur some innovation along the way. :)

-Trevor
 




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