Re: [avr-libc-dev] Doing my own Tiny2313/Tiny13 libraries?

[Joerg Wunsch]

As Bob Paddock wrote:

> However my boss is about is about to start his first project using
> the Tiny2313 and the first time using GCC.  I know his legacy code
> is far more complex, but it is also already crammed full in the
> 90S2313.  Anything that makes the code bigger will be a Bad Thing.

It should not become bigger by reverting to the AT90S2313 code
generator, but you're going to miss the possible space saving that
could result from the use of MOVW.

> I have seen mentioned that there is a possibility of creating
> per-devices libraries to solve the MUL problem.  Is this something I
> can do myself?  What do I need to do?

It's less a matter of per-device libraries but rather of modifying the
compiler to understand a new `architecture' so for the 'tiny2313, MOVW
could be used but MUL avoided.  Right now, they are tied together
inside GCC into one `architecture' (avr4).

Are you prepared to compile your own compiler?  If so, if you fail to
work with the current compiler, and it turns out that the few bytes of
space saved by using MOVW could become a real issue, it should always
be possible to send you a source code patch.  The patch needs to be
done for GCC anyway, sooner or later.

-- 
cheers, J"org               .-.-.   --... ...--   -.. .  DL8DTL

http://www.sax.de/~joerg/                        NIC: JW11-RIPE
Never trust an operating system you don't have sources for. ;-)