Re: hardware + Lua resources

On Sat, Feb 12, 2011 at 16:55, Ivan Baggett <ibaggett@bagotronix.com> wrote:

And yet, still no PIC32 support.

Yes, for the (we-can't-pay-for-every-number-of-kits-necessary-for-the-ports-we-do) reasons that Bogdan has mentioned and also because users have commented on our list that an initial PIC32 port was to be started.
We try to concentrate now on the core functionality, on new eLua features, on more doc and on some refactoring to make it easier for the final users. New ports and the enhancing of existing modules can count on the community, specially on those that will make commercial uses of them.

IIRC, I started this thread a few months
ago by asking if anyone had added PIC32 to the list of ported chips. Yes,
I know, do it yourself...story of my life.

Another option is to be part of a open-source project with true distributed and collaborative development model and share your thoughts. Some of our ports had their priorities decided by the community, some others were triggered by simple would-like-to-have comments on the list and all of them have code contributions from the whole community.

PIC32 can be had with up to 512K flash, 128K RAM.

As well as some others, including the new Kinetis Cortex-M4 from Freescale and, to mention another architecture, Atmel's AVR32 (which is being used on the open-hardware Mizar32 Italian design from SimpleMachines). I think STM32 models are getting there too.

And built-in ethernet
MAC. I once tried to start a design with a Luminary ARM chip, but found
there was (at that time) no stock and long lead times, so I had to pick
another chip. PIC32 was that chip.

True, LM3S Cortex-M3 lacks a bit of RAM but they were the first to release a Cortex-M3 core with enough memory to happily run eLua and they were quite ahead at the time. This resulted in nothing less than Texas Instruments buying Luminary Micro. They have already launched chips with 96KB or RAM (the 989B series) and more is on the way.

--
Best regards,
Ivan Baggett

Best regards
Dado

> On Wed, Dec 29, 2010 at 10:37, Roberto Ierusalimschy
> <roberto@inf.puc-rio.br
>> wrote:
>
>> > > but a language that
>> > > calls itself small and embeddable (i.e. Lua) should really be that.
>> >
>> > With Lua, small and embeddable doesn't necessarily mean hardware.
>> > Most of the time small is relative to desktop/laptop type computers,
>> > including small ones and embeddable refers to embedding within a
>> > larger application.
>>
>> Actually, "embeddable" has two quite different meanings, but Lua is
>> embeddable in both of them. A lot of non desktop/laptop type computers
>> uses Lua currently.
>>
>
> Right and I would add to it that the small footprint of Lua is very well
> suited for embedding on bare-metal (which is what we do in

> eLua<http://www.eluaproject.net>)

> but, of course for the good reasons and great performance, the RAM usage
> is
> sometimes "hungry". eLua already has some extensions (ie: romable tables
> and
> functions, emergency garbage collection, ...) to make life easier on the
> current embedded hardware constraints.
>
> And "small" is not relative to desktop/laptop type computers. Even for a
>> very small laptop, if Lua grew ten fold, from its current ~200KB to 2MB,
>> it would make no difference at all.
>>
>
> Yes, but it would break the statement that it is embeddable in both of the
> cases as mentioned.
> Although microcontrollers' hardware has been growing very fast lately, the
> average ROM capacity on commercial dev kits are around the 256KBytes
> (largely enough for eLua and we have support for sd/mmc cards and other
> filesystems) and RAM around 128KBytes (enough for simple and medium size
> applications). There are some MCUs on the market (and many announced for
> soon) with 1MB++ ROM and 512KB++ RAM. Clock frequencies are already ok and
> won't stop to grow for a while.
> A ten fold growth of Lua's footprint would be very bad for eLua and I hope
> this is not on Lua's roadmap :) :)
>
> The current eLua supported platforms, architectures, peripherals and
> features can be seen here http://www.eluaproject.net/en_status.html
>
> Details on using eLua on supported kits and a (user editable) wish list of
> new platforms are on our wiki at http://wiki.eluaproject.net/Boards
>
> -- Roberto
>>
>
> Dado
>