PUPDevice support for custom ID

[JorgePe]

Hi!
I've been using an ESP32 with MyOwnBricks (https://github.com/ysard/MyOwnBricks) to learn how to create my own sensors.
Emulating a Tilt Sensor was easy, just needed to adapt the author code to work with ESP32 UART#1

Now I want to test a simple ON/OFF switch so I created a crippled Tilt Sensor, with just one mode (0) that reads just one int8. I named it 'MYOWNSWITCH' and used the same ID as the Tilt Sensor.

PUPDevice recognizes it fine:

{'id': 34, 'modes': (('MYOWNSWITCH', 1, 0),)}

and I can read the state of a GPIO pin on the ESP32 and send '0' when it is LOW and '100' when it is HIGH, good enough, can map those values to ON/OFF or anything else in my Pybricks script:

device = PUPDevice(Port.A)
print(device.info())
while(True):
    if device.read(0)[0] == 100:
        print('ON')
    else:
        print('OFF')
    wait(1000)

But If I change the ID for an unknown device (like '99') then PUPDevice cannot recognize it (OSError: [Errno 19] ENODEV).
I also tried using the Force Sensor ID and then it works again, so it looks like PUPDevice only accepts known device IDs?

I am just changing the CMD_TYPE message like this:

  SerialTTL.write("\x40\x3F\x80", 3);                           // CMD_TYPE, Type ID: 0x3F = 63 = Force Sensor   OK
  SerialTTL.write("\x40\x22\x9D", 3);                          // CMD_TYPE, Type ID: 0x22 = 34 = Tilt Sensor       OK
  SerialTTL.write("\x40\x63\xDC", 3);                          // CMD_TYPE, Type ID: 0x63 = 99 = N/A                   NOK

Is there a way to assign custom ID's?

[dlech]

Does it work if you use an unassigned number between two known numbers, like 36?

The enum we are currently using doesn't reserve any space for higher numbers, so picking a random number like 99 could actually coincide with something else.

[JorgePe]

It works.

{'id': 36, 'modes': (('MYOWNSWITCH', 1, 0),)}

I only tried values well above 64 to avoid collision with known devices (https://docs.pybricks.com/en/stable/iodevices/pupdevice.html) but never bellow.

And it makes more sense to use lower values for my custom devices, future LEGO releases will probably just keep increasing their IDs, eventually leaving some gaps.

Real neat feature, this PUPDevice class. Support for generic UART devices would also be great (not sure about current state of development) but at least I finally found a way to use the SPIKE distance sensor backpack for my own purposes.

Many thanks!