The master_clock_pin was already optional, but not specifying it would
result in a crash. This fixes it, so it really can be omitted, when the
camera module has its own clock source built in.
Originally, black_bindings found each contiguous "//|" block and sent
it to black independently. This was slower than it needed to be.
Instead, swap the comment prefix: when running black, take off
"//|" prefixes and put "##|" prefixes on all un-prefixed lines.
Then, after black is run, do the opposite operation
This more than doubles the overall speed of "pre-commit run --all",
from 3m20s to 55s CPU time on my local machine (32.5s to under 10s
"elapsed" time)
It also causes a small amount of churn in the bindings, because
black now sees enough context to know whether one 'def' follows another
or ends the 'def's in a 'class'. In the latter case, it adds an extra
newline, which becomes a "//|" line.
I'm less sure why a trailing comma was omitted before down in
rp2pio/StateMachine.c but let's roll with it.
This uses the esp32-camera code instead of our own homebrewed camera code.
In theory it supports esp32, esp32-s2 and esp32-s3, as long as they have
PSRAM.
This is very basic and doesn't support changing any camera parameters,
including switching resolution or pixelformat.
This is tested on the Kaluga (ESP32-S2) and ESP32-S3-Eye boards.
First, reserve some PSRAM by putting this line in `CIRCUITPY/_env`:
```
CIRCUITPY_RESERVED_PSRAM=524288
```
and hard-reset the board for it to take effect.
Now, the following script will take a very low-resolution jpeg file and print
it in the REPL in escape coded form:
```python
import board
import esp32_camera
c = esp32_camera.Camera(
data_pins=board.CAMERA_DATA,
external_clock_pin=board.CAMERA_XCLK,
pixel_clock_pin=board.CAMERA_PCLK,
vsync_pin=board.CAMERA_VSYNC,
href_pin=board.CAMERA_HREF,
pixel_format=esp32_camera.PixelFormat.JPEG,
i2c=board.I2C(),
external_clock_frequency=20_000_000)
m = c.take()
if m is not None:
print(bytes(m))
```
Then on desktop open a python repl and run something like
```python
>>> with open("my.jpg", "wb") as f: f.write(<BIG PASTE FROM REPL>)
```
and open my.jpg in a viewer.
