Re: Speed comparison: WP 34s v2.2 vs. v3.1 Message #9 Posted by Marcus von Cube, Germany on 8 Dec 2012, 4:27 a.m., in response to message #8 by Walter B
Walter, but does it matter? I agree that computing times of more than a second for a 'built-in' function (phi^-1) are annoying and can be addressed but the overall speed of the device is still 'good enough'.
TICKS is probably not the best way to measure speed when no crystal is installed. It's better to call the function in a loop and use a stop watch.
A general remark to the execution speed of user (or XROM) code:
- We made the register addressing much more versatile in V3 compared to V2. What used to be a simple array access must now take into account varying register sizes and allocations and needs to cope with local addressing. This adds to each and every register access, even when it goes to the stack.
- If the chip had double the flash size we could make it almost double the speed just by getting rid of thumb mode and all the ridiculously crude space optimizations we did. Alas, the code needs to live in less than 128K... And it does!
Sacrificing library space down to the size of the present library isn't the best idea. The library is meant to be the user's program storage area. The library code provided is just an example what can be done and by no means to be regarded as complete.
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