Hello, On Wed, 24 Jun 2015 12:40:10 +0200 Antoine Pitrou <solipsis@pitrou.net> wrote:
On Wed, 24 Jun 2015 13:13:49 +0300 Paul Sokolovsky <pmiscml@gmail.com> wrote:
So, the question is not how to "appropriate for precise datetime computations" - MicroPython inherits that ability by being a Python, but how to scale into the opposite direction, how to integrate into stdlib "realtime" time handling, which is simple, fast (getting timing value itself is low-overhead) and modular-arithmetic by its nature.
I'm sorry, I don't understand. If you have 64-bit ints then why would you use anything smaller for timestamps?
Because MicroPython stays close (== may stay close) to hardware and does not depend on any OS (even those smaller embedded OSes, which are called RTOS'es). Then, it's usual case for embedded hardware to have hardware timers of the same size or smaller as the architecture machine word. For example, on a 32-bit CPU, timers are usually 32-, 24-, or 16- bit. On 16-bit CPUs, timers are 16- or 8-bit. Put it otherwise way, there's simply nowhere to get 64-bit time value from, except by building software abstractions, and MicroPython does not *require* them (if they exist - good, they will be helpful for other things, if not - MicroPython can still run and do a large subset of useful things). Another reason is that MicroPython exactly uses tagged pointers scheme, and small integers are value, not reference, objects. Dealing with them is largely faster (MicroPython easily beats CPython on (small) integer performance), and doesn't require memory allocation (the latter is another important feature for embedded systems).
Regards
Antoine.
-- Best regards, Paul mailto:pmiscml@gmail.com