GTA03 LED controller: LP5521

andrzej zaborowski balrogg at
Tue Nov 18 10:18:12 CET 2008


2008/11/18 Werner Almesberger <werner at>:
> This is a discussion that started on an internal list but that really
> ought to be public. So I'm dragging it here, kicking and screaming ...
> In GTA03, we'll use the following controller chip for some LEDs:
> One thing that's interesting about it is that it can be programmed
> in some form of primitive assembler language. National magnificently
> call the tool to translate this language to its binary representation
> a "compiler".
> There's been concern about whether National would give us the right
> to redistribute their Windows-based compiler. However, since the
> translation task seems to be more than trivial, I think we're better
> off just rewriting the thing from scratch.
> To make a nice parser in little time, lex and yacc are useful. Here's
> an example using them:
> The above example also shows how one can easily add cpp to one's
> parser. That way, the usual convenience items (comments, macros, and
> include files) are taken care of.
> Some people have suggested that the translator is so simple that one
> should even put it into the kernel ...

linux-omap-2.6 people thought so and made a very simple interface for
programming the lp5521 where the compilation is left to be done in
user's head.  It's described in this mail:
Obviously it's very limited compared to your compiler, I find the
compiler very cool.  (Is it turing complete? ( - assuming that cpp

Their driver is at;a=blob;f=drivers/i2c/chips/lp5521.c;h=c0862d9f2690f0f0daa38f21659aed7011dff175;hb=HEAD
, I don't know if you planned to use it.


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