Re: Lua on Microcontrollers

[Doug Currie <doug.currie@...>]

On Dec 10, 2013, at 5:48 AM, John Hind <john.hind@zen.co.uk> wrote:

> I have been wondering how difficult it would be to modify the Lua memory allocator so it could split the Lua State between Flash and RAM. This way, most of the less volatile memory such as strings, function bytecodes and library tables could be located in more plentiful flash memory reserving RAM for what really needs it.

See: http://www.eluaproject.net/doc/v0.9/en_arch_ltr.html

for a description of the eLua LTR (Lua Tiny RAM) patch. It implements ROM based

	• lightfunctions: these are "simple" functions, in the sense that they can't have upvalues or environments. They are just pointers to regular C functions. Other than that, you can use them from Lua just as you'd use any other function.

	• rotables: these are read-only tables, but unlike the read-only tables that one can already implement in Lua with metamethods, they have a very specific property: they don't need any RAM at all. They are fully constant, so they can be read directly from ROM.

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