Re: Lua on Microcontrollers

On Wed, Dec 11, 2013 at 3:49 PM, Justin Cormack <justin@specialbusservice.com> wrote:

On 11 Dec 2013 09:57, "Bogdan Marinescu" <bogdan.marinescu@gmail.com> wrote:
>
> Hi John,
>
>
> On Wed, Dec 11, 2013 at 11:37 AM, John Hind <john.hind@zen.co.uk> wrote:
>>
>> > Date: Tue, 10 Dec 2013 21:09:44 +0200
>> > From: Bogdan Marinescu <bogdan.marinescu@gmail.com>
>> > Subject: Re: Lua on Microcontrollers
>>
>> > About memory, 2M or even 1M of RAM is enough to implement quite a bit
>> > of functionality with eLua. And there are also MCUs that can work with
>> > SDRAM
>> > memory:
>> >
>> > http://www.embeddedartists.com/products/boards/lpc4088_qsb.php
>> >
>> > That thing has 32M of SDRAM, which is more than enough for any embedded
>> > Lua application that I can think of.
>> > And there is also this:
>> >
>> > http://am.renesas.com/products/mpumcu/rz/rza/rza1/index.jsp
>> >
>> > All in all, internal RAM is evolving in the correct direction for eLua.
>>
>> Hi Bogdan,
>>
>> I'd not realised you were still actively developing eLua.
>>
>> Have you considered a port of eLua onto Raspberry Pi and/or Beaglebone Black? Of course, Lua can easily be installed on these under Linux, but I mean running "bare metal" without an OS. So it would just be a route to getting a low-cost target board with plenty of RAM. The "microcontroller + SDRAM" boards all seem to be very poor value compared to these little Linux boards.
>
>
> That's true. I've been seriously considering a port to the BBB, since TI provides a framework for writing bare-metal apps on the BBB, but never found the time to do it. When I'm doing now is porting Lua 5.2 on top of the mbed framework (http://www.mbed.org), which has a large range of libraries and a growing platform support. This would allow me to focus on the actual embedded Lua core, without having to worry about porting to a new platform, which is a huge advantage.

I keep hearing about mbed but all the boards I see have 8k of Ram. I presume there are some with more but if someone could point them out that would be useful!

The board that I've pointed to eariler is mbed enabled:

http://www.embeddedartists.com/products/boards/lpc4088_qsb.php

List of officialy supported mbed platforms (others are available, but not yet official):

https://mbed.org/platforms/

Full list of targets (you can see there that some preliminary suppor for STM32F4 also exists):

https://github.com/mbedmicro/mbed/blob/master/workspace_tools/targets.py

Best,

Bogdan

Justin

>>
>>
>> Of course if the single chip microcontrollers get up to a few M RAM rather than a few hundred K as at present, the problem would go away, but we do seem to have been waiting a long time for this now.
>
>
> That's true. I think we're going there, but the wait is not over.
>
>>
>>
>> The thing I really like about the MicroPython approach is the composite USB device: it presents for development as both a serial console port and a mass storage device. This allows editing of scripts directly on the device from any host computer without having to faf about with file transfer over a serial link.
>
>
> That's something doable with current eLua, at least on some of the platforms. Shouldn't even be that difficult, some manufacturers provide very good USB libraries.

>
> Best,
> Bogdan
>
>>
>>
>> - John
>>
>>
>>
>> ---
>> This email is free from viruses and malware because avast! Antivirus protection is active.
>> http://www.avast.com
>>
>>
>