The bit-bang implementation was replaced with the RMT implementation in
599b61c086. This commit brings back that
bit-bang code, and allows it to be selected via the new static method:
esp32.RMT.bitstream_channel(None)
The bit-bang implementation may be useful if the RMT needs to be used for
something else, or if bit-banging is more stable in certain applications.
Signed-off-by: Damien George <damien@micropython.org>
Save and restore the same duty cycle when the frequency (or frequency
resolution) is changed. This allows a smooth frequency change.
Also update the esp32 PWM quickref to be clearer.
The methods duty_u16() and duty_ns() are implemented to match the existing
docs. The duty will remain the same when the frequency is changed.
Standard ESP32 as well as S2, S3 and C3 are supported.
Thanks to @kdschlosser for the fix for rounding in resolution calculation.
Documentation is updated and examples expanded for esp32, including the
quickref and tutorial. Additional notes are added to the machine.PWM docs
regarding limitations of hardware PWM.
Anywhere a module is mentioned, use its "non-u" name for consistency.
The "import module" vs "import umodule" is something of a FAQ, and this
commit intends to help clear that up. As a first approximation MicroPython
is Python, and so imports should work the same as Python and use the same
name, to a first approximation. The u-version of a module is a detail that
can be learned later on, when the user wants to understand more and have
finer control over importing.
Existing Python code should just work, as much as it is possible to do that
within the constraints of embedded systems, and the MicroPython
documentation should match the idiomatic way to write Python code.
With universal weak links for modules (via MICROPY_MODULE_WEAK_LINKS) users
can consistently use "import foo" across all ports (with the exception of
the minimal ports). And the ability to override/extend via "foo.py"
continues to work well.
Signed-off-by: Jim Mussared <jim.mussared@gmail.com>
This commit adds I2S protocol support for the esp32 and stm32 ports, via
a new machine.I2S class. It builds on the stm32 work of blmorris, #1361.
Features include:
- a consistent I2S API across the esp32 and stm32 ports
- I2S configurations supported:
- master transmit and master receive
- 16-bit and 32-bit sample sizes
- mono and stereo formats
- sampling frequency
- 3 modes of operation:
- blocking
- non-blocking with callback
- uasyncio
- internal ring buffer size can be tuned
- documentation for Pyboards and esp32-based boards
- tested on the following development boards:
- Pyboard D SF2W
- Pyboard V1.1
- ESP32 with SPIRAM
- ESP32
Signed-off-by: Mike Teachman <mike.teachman@gmail.com>