Move the API to the end, recipes all grouped together up-front (with
remote GPIO setup just before the remote GPIO recipes). Tweak some
headings so everything looks a little more consistent in the (now
shorter) ToC.
Also added module index tags.
Add epub output, fix PDF output to include page-numbers in links (for
printed output), reduce the (now ridiculous) length of the ToC by
dropping it to one level, add numbering to chapters
This is almost a straight copy'n'paste of picamera's development chapter
with a few minor changes to make it read sensibly for GPIO Zero; it
needs plenty more work to fulfil the goals of #451 but hopefully this'll
act as a reasonable base for people to work on.
While the tests work well on a PC or Travis, the Pi (where I ought to be
running them!) has some issues with the timing tests. Need to relax the
tolerance of the "assert_states_and_times" method to 0.05 seconds
otherwise it periodically fails even on something reasonably quick like
a Pi 2 (less failures on a Pi 3 but still occasionally).
Also reduced default fps to 25; if the default timing occasionally fails
on a Pi 2 it's evidently too fast for a Pi 1 and shouldn't be the
default; 25 also doesn't look any different to me on a pulsing LED.
There's also a bunch of miscellaneous fixes in here; last minute typos
and chart re-gens for the 1.2 release.
Me and my big mouth. No sooner do I declare the base classes "relatively
stable" than I go and mess around with it all again. Anyway, this is the
long promised set of utilities to make source/values more interesting.
It includes a few interesting little utility functions, a whole bunch of
examples and introduces the notion of "pseudo" devices with no (obvious)
hardware representation like a time-of-day device.
This necessitated making the event system a little more generic (it's
not exclusive the GPIO devices after all; no reason we can't use it on
composite devices in future) and by this point the mixins have gotten
large enough to justify their own module.
The pseudo-devices are a bit spartan and basic at the moment but I'm
sure there'll be plenty of future ideas...
This PR adds a software SPI implementation. Firstly this removes the
absolute necessity for spidev (#140), which also means when it's not
present things still work (effectively fixes#185), and also enables any
four pins to be used for SPI devices (which don't require the hardware
implementation).
The software implementation is simplistic but still supports clock
polarity and phase, select-high, and variable bits per word. However it
doesn't allow precise speeds to be implemented because it just wibbles
the clock as fast as it can (which being pure Python isn't actually that
fast).
Finally, because this PR involves creating a framework for "shared"
devices (like SPI devices with multiple channels), it made sense to bung
Energenie (#69) in as wells as this is a really simple shared device.
This commit is a fairly major piece of work that abstracts all pin
operations (function, state, edge detection, PWM, etc.) into a base
"Pin" class which is then used by input/output/composite devices to
perform all required configuration.
The idea is to pave the way for I2C based IO extenders which can present
additional GPIO ports with similar capabilities to the Pi's "native"
GPIO ports. As a bonus it also abstracts away the reliance on the
RPi.GPIO library to allow alternative pin implementations (e.g. using
RPIO to take advantage of DMA based PWM), or even pure Python
implementations.
