A couple of things 43s related

[Claudio L.]

(03-02-2015 06:10 AM)MarkHaysHarris777 Wrote:  I'm definitely going to play with one of these soon. I am suspicious that this 'teensy' board will have speed stepping or at least a way to reduce the main clock (the WP34s 'SLOW' mode) which will reduce the current drain; most of the time we really don't need the ARM to be running so dang fast that it sucks our batts dry...

All ARM chips have variable clock speed, you can program it at will on software (look for PLL control registers on the SoC datasheet).
Also, while waiting for the user to press a key (which in a calculator will be 99.9% of the time), use the "Wait-for-interrupt" CPU instruction, which freezes the CPU to a very low-power state until an interrupt is triggered.
That alone can save a lot of power.

Claudio