next-generation (now) MPU discussion / RAM/ROM-size requirements

Werner Almesberger werner at
Thu Apr 24 09:42:56 CEST 2008

Andy Green wrote:
> Well fine, but what does giving the MSP430 the battery backup actually
> get us?

Allow us to get out of PMU.Standby, maintain GPIOs while in PMU.Standby,

> Exactly, this is the reason behind the "core" concept.  We need the core
> to be deployable in any reasonable "clothes" like LCM, physical
> dimensions, etc.  So it doesn't delay us that the LCM is not decided, we
> design the core to not depend on particular display.

Hmm, we can actually apply this to the MPU as well. Since our first
round of devices will be throw-away anyway, because the LCM will
change, we may as well err towards having too potent an MPU. If we
then find out that we only need a small fraction of its capabilities,
we can always specify a simpler model from the same family. (And
develop the code for it on the big one.)

So thumbs up from me for a big MPU in our first GTA04 spin.

Now, once thing that worries me a bit is that supposedly some of these
MPUs aren't supported by gcc. (I think Milosch once mentioned that.)
We have to find out if this is the case with the proposed chip.

- Werner

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