Making the Firmware Image File for Pybricks Micropython V2.0.0 for EV3

[NabeelZ-KA]

Hello!!

I am in dire need of help. I've been trying to find a firmware that would actually work well for our needs, and pybricks seems to be the best one. However, there are a few problems, but that required me to try to mess with the source code of the image, mainly it's that we need a the raw RGB color values, instead of the percentages that pybricks gives us. So I downloaded the source code, and messed with the modev3devices.c in the extmod folder

STATIC mp_obj_t ev3devices_ColorSensor_raw_rgb(mp_obj_t self_in) {
    ev3devices_ColorSensor_obj_t *self = MP_OBJ_TO_PTR(self_in);
    int32_t rgb[3];
    pbdevice_get_values(self->pbdev, PBIO_IODEV_MODE_EV3_COLOR_SENSOR__RGB_RAW, rgb);

    mp_obj_t tup[3];
    for (uint8_t i = 0; i < 3; i++) {
        tup[i] = mp_obj_new_int(rgb[i]);
    }
    return mp_obj_new_tuple(3, tup);
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(ev3devices_ColorSensor_raw_rgb_obj, ev3devices_ColorSensor_raw_rgb);

STATIC const mp_rom_map_elem_t ev3devices_ColorSensor_locals_dict_table[] = {
    { MP_ROM_QSTR(MP_QSTR_reflection), MP_ROM_PTR(&ev3devices_ColorSensor_reflection_obj) },
    { MP_ROM_QSTR(MP_QSTR_ambient   ), MP_ROM_PTR(&ev3devices_ColorSensor_ambient_obj)    },
    { MP_ROM_QSTR(MP_QSTR_color     ), MP_ROM_PTR(&ev3devices_ColorSensor_color_obj)      },
    { MP_ROM_QSTR(MP_QSTR_rgb       ), MP_ROM_PTR(&ev3devices_ColorSensor_rgb_obj)        },
    { MP_ROM_QSTR(MP_QSTR_raw_rgb), MP_ROM_PTR(&ev3devices_ColorSensor_raw_rgb_obj) },
};
STATIC MP_DEFINE_CONST_DICT(ev3devices_ColorSensor_locals_dict, ev3devices_ColorSensor_locals_dict_table);

However, when I try to make the file. (using make ev3dev-armel), I either get

ERROR: failed to build: failed to solve: process "/bin/sh -c sudo apt-get update && DEBIAN_FRONTEND=noninteractive sudo apt-get install --yes --no-install-recommends alsa-utils build-essential espeak ev3dev-media ev3dev-mocks git libasound2-plugin-ev3dev libasound2-plugin-ev3dev:armel libasound2:armel libc6-dbg:armel libffi-dev:armel libglib2.0-0-dbg:armel libgrx-3.0-2-dbgsym:armel libgrx-3.0-dev:armel libi2c-dev libmagickwand-6.q16-3:armel libsndfile1:armel libudev-dev:armel libumockdev0:armel pkg-config python python3 uthash-dev:armel xfonts-100dpi" did not complete successfully: exit code: 100

if I run it from CLion, or if I run it from WSL, I get

[Username]@[Laptop ID]:/mnt/c/Users/[Username]/CLionProjects/pybricks-micropython$ make ev3dev-armel
/bin/sh: 2: bricks/ev3dev/docker/setup.sh: not found
make: *** [Makefile:20: ev3dev-armel] Error 127

Even though setup.sh exists

(And yes I did try to pull ev3dev/debian-stretch-cross, and I did compile micropython)

I am at a loss on what to do please help

P.S.

I also tried using pybricksdev but it didn't work either:

C:\Users\[Username]>pipx run pybricksdev flash C:\Users\[Username]\CLionProjects\pybricks-micropython.zip
⚠️ pybricksdev is already on your PATH and installed at
C:\Users\[Username]\AppData\Roaming\Python\Python312\Scripts\pybricksdev.EXE. Downloading and running anyway.
Creating firmware...
Traceback (most recent call last):
File "", line 198, in run_module_as_main
File "", line 88, in run_code
File "C:\Users\[Username]\pipx.cache\17d81503600c4f3\Scripts\pybricksdev.exe_main.py", line 6, in
File "C:\Users\[Username]\pipx.cache\17d81503600c4f3\Lib\site-packages\pybricksdev\cli_init.py", line 559, in main
asyncio.run(subparsers.choices[args.tool].tool.run(args))
File "C:\Program Files\Python312\Lib\asyncio\runners.py", line 194, in run
return runner.run(main)
^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\asyncio\runners.py", line 118, in run
return self.loop.run_until_complete(task)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\asyncio\base_events.py", line 687, in run_until_complete
return future.result()
^^^^^^^^^^^^^^^
File "C:\Users\[Username]\pipx.cache\17d81503600c4f3\Lib\site-packages\pybricksdev\cli\flash.py", line 434, in flash_firmware
firmware, metadata, license = await create_firmware_blob(firmware_zip, new_name)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\[Username]\pipx.cache\17d81503600c4f3\Lib\site-packages\pybricksdev\firmware.py", line 269, in create_firmware_blob
with archive.open("firmware.metadata.json") as f:
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\zipfile_init.py", line 1604, in open
zinfo = self.getinfo(name)
^^^^^^^^^^^^^^^^^^
File "C:\Program Files\Python312\Lib\zipfile_init_.py", line 1532, in getinfo
raise KeyError(
KeyError: "There is no item named 'firmware.metadata.json' in the archive"

P.P.S.
How so I edit the python library so that it doesn't show up as an error in VS Code? So that I can actually run my custom functions

can I just add this to C:\Users\[Username]\AppData\Roaming\Python\Python312\site-packages\pybricks\ev3devices\__stub\__colorsensor.py

    def raw_rgb(self) -> Tuple[int, int, int]:
        return (0, 0, 0)

P.P.P.S
The reason I need the raw values is because, for some reason, the transformation of the RGB values from 0 - 1020 to percentages messes things up when you are trying to look at colors from a distance. In EV3-G and dEV3Dev-Python, I was able to get good raw RGB (or usually HSV) values using either a custom block, or the built in functions. However, in pybricks, that doesn't seem to be the case, and when the color sensor is far (e.i. at the same distance it was when we were using EV3-G and EV3Dev), it would just give us (0, 0, 0). If there is any other way around this that would be greatly appreciated because neither EV3-G nor Ev3Dev work for us. Adjusting the firmware is preferable, because I also tried to add a gyro calibrate function as well in \extmod\modev3devices.c:

#include "py/mphal.h" // for mp_hal_delay_ms

STATIC mp_obj_t ev3devices_GyroSensor_calibrate(mp_obj_t self_in) {
    ev3devices_GyroSensor_obj_t *self = MP_OBJ_TO_PTR(self_in);

    // Step 1: Save current mode
    int32_t dummy;
    pbdevice_get_values(self->pbdev, PBIO_IODEV_MODE_EV3_GYRO_SENSOR__ANG, &dummy);

    // Step 2: Set CAL mode (trigger calibration)
    pbdevice_get_values(self->pbdev, PBIO_IODEV_MODE_EV3_GYRO_SENSOR__CAL, &dummy);

    // Step 3: Wait 2 seconds
    mp_hal_delay_ms(2000);

    // Step 4: Reset offset to zero
    self->offset = 0;

    return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_1(ev3devices_GyroSensor_calibrate_obj, ev3devices_GyroSensor_calibrate);

STATIC const mp_rom_map_elem_t ev3devices_GyroSensor_locals_dict_table[] = {
    { MP_ROM_QSTR(MP_QSTR_angle),       MP_ROM_PTR(&ev3devices_GyroSensor_angle_obj)       },
    { MP_ROM_QSTR(MP_QSTR_speed),       MP_ROM_PTR(&ev3devices_GyroSensor_speed_obj)       },
    { MP_ROM_QSTR(MP_QSTR_reset_angle), MP_ROM_PTR(&ev3devices_GyroSensor_reset_angle_obj) },
    { MP_ROM_QSTR(MP_QSTR_calibrate), MP_ROM_PTR(&ev3devices_GyroSensor_calibrate_obj) },
};
STATIC MP_DEFINE_CONST_DICT(ev3devices_GyroSensor_locals_dict, ev3devices_GyroSensor_locals_dict_table);

Should I also add this in C:\Users\[Username]\AppData\Roaming\Python\Python312\site-packages\pybricks\ev3devices\__stub\__gyrosensor.py

    def calibrate(self):
        ...

[dlech]

You should be able to use the LumpDevice class to get direct access to all sensor modes without having to compile anything.

[dlech]

Yes, The link is for the docs for Pybricks v2.0 so everything there applies to EV3/ev3dev.

[NabeelZ-KA]

With a bit of trial and error, mode 4 seems to the be the raw rgb values. Are these the actual rgb values that go from 0 to 1020?

[dlech]

Yes, that is the RAW RGB mode.

You can find a list of the modes here: https://github.com/pybricks/pybricks-micropython/blob/24881534290203ac1b0813d3346cd89f44416256/lib/lego/lego/device.h#L164

[NabeelZ-KA]

Thank you so much!!

I was also able to get it working with the Ev3devSensor class.

I was also just wondering if there is any way to calibrate (not just reset), the gyro sensor in pybricks. Because in ev3dec you can call calibrate(), and in ev3-g you can try to access it as an infrared sensor then wait. Is there any way to do this in pybricks?

I believe this is done by changing the mode of the sensor to 'CAL' or smth then waiting then putting it back to it's original mode, atleast in ev3dev. The infrared thing in ev3-g I think simulates this. Therefore, is there any way to mimic this type of interaction with pybricks. Because I can only really read with the Ev3devSensor class.

[dlech]

There are a couple of different hardware revisions of the EV3 gyro sensor. On the older ones, switching modes could cause the sensor to restart, but on newer ones changing the mode of the port is needed to get the sensor to restart. There isn't a difference between "calibrating" and "resetting" for the EV3 gyro sensor. To do one, you have to do the other.

@laurensvalk probably remembers better than me what we figured out was the best way to accomplish this.