LCD-TFT Driver Controller (LTDC)
Re: LCD-TFT Driver Controller (LTDC)
The following text is a result of a conversation between inmarket and me:
It has been asserted that uGFX cannot be linked with ChibiOS. That however is incorrect under the stable ChibiOS license due to the linking exception. uGFX is not a "binary" library, it is a collection of source code. It also is not distributed as a "combined work" and can therefore be linked with ChibiOS. Note that the ChibiOS HAL (under the Apache license) is also not GPL and if linking with non-GPL code was not allowed then ChibiOS could not link with its own HAL.
The reality is that the uGFX developers have spent considerable time and money developing the source code. We believe in open source but also believe that if you are going to profit commercially from our work you should contribute in like manner (with licensing fees) to uGFX. Note that we offer free licenses for open-hardware projects.
Our choice may not be your choice but it is our decision, just as Giovanni chooses how he wants to license his great product.
~ Tectu
It has been asserted that uGFX cannot be linked with ChibiOS. That however is incorrect under the stable ChibiOS license due to the linking exception. uGFX is not a "binary" library, it is a collection of source code. It also is not distributed as a "combined work" and can therefore be linked with ChibiOS. Note that the ChibiOS HAL (under the Apache license) is also not GPL and if linking with non-GPL code was not allowed then ChibiOS could not link with its own HAL.
The reality is that the uGFX developers have spent considerable time and money developing the source code. We believe in open source but also believe that if you are going to profit commercially from our work you should contribute in like manner (with licensing fees) to uGFX. Note that we offer free licenses for open-hardware projects.
Our choice may not be your choice but it is our decision, just as Giovanni chooses how he wants to license his great product.
~ Tectu
- Giovanni
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Re: LCD-TFT Driver Controller (LTDC)
Careful, I was not talking about ChibiOS but GPL code in general.
The ChibiOS exception does allow linking of proprietary code to stable versions without having to disclose source code but source code disclosure has never been a problem in your case.
Giovanni
The ChibiOS exception does allow linking of proprietary code to stable versions without having to disclose source code but source code disclosure has never been a problem in your case.
Giovanni
Re: LCD-TFT Driver Controller (LTDC)
Yes, pure GPL is a problem for just about every other license. Unfortunate.
Re: LCD-TFT Driver Controller (LTDC)
That's why we chose a revised BSD license for our free projects
Anyway, I'm having some trouble while trying to make my demo code work. I'm trying to debug the ST demo code step-by-step, since I cannot even change the background color of the LCD, which implies I can't test my LTDC driver for now.
Anyway, I'm having some trouble while trying to make my demo code work. I'm trying to debug the ST demo code step-by-step, since I cannot even change the background color of the LCD, which implies I can't test my LTDC driver for now.
Re: LCD-TFT Driver Controller (LTDC)
TexZK wrote:That's why we chose a revised BSD license for our free projects
I agree. The "problem" is that both, ChibiOS and uGFX, may have once started as a spare time project but have clearly developed into something with commercial potential (ChibiOS is of course a lot further).
~ Tectu
Re: LCD-TFT Driver Controller (LTDC)
And both projects now take considerable investment in time (and therefore money) to grow.
Re: LCD-TFT Driver Controller (LTDC)
Voilà , first screenshot of a meaningful texture displayed through the LTDC driver
I have to figure out why the texture is shifted. There could be some inconsistencies with the computation of LCD offsets (front-/back-porch) or similar things. I'll inspect the ST demo to see where I'm doing it wrong.
I have to figure out why the texture is shifted. There could be some inconsistencies with the computation of LCD offsets (front-/back-porch) or similar things. I'll inspect the ST demo to see where I'm doing it wrong.
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- XOR texture with Wolf3D palette
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Re: LCD-TFT Driver Controller (LTDC)
Good work! Happy to see the first usable HAL in action on my board
~ Tectu
~ Tectu
- Giovanni
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