pauli5

How long until purchasing from an AI ad gives you token credits I wonder.

With a materials to retail cost multiplier of x10 (which is on the low side), your system wouldn't be cheaper than the commercial one unless you can build and install it yourself. I doubt most centres would have the skills available to do this.

Nonetheless, you've done a fantastic job here.

Yes, it's the DM42n hardware underneath. The keyboard and overlay are different and the firmware is written from scratch using the WP 34S mathematics code. This has a lot more functionality than the DM42n does.

Correct.

Floats support both -0 and 0 they compare equal but their bit representations don't. Zero can be tricky.

Not a numbers (NaNs) always compare as false. Their bit representations won't.