Pybricks for NXT

[skippa]

Hi folks, just wondering if anyone got pybricks to work with the NXT brick? I read the nxos repo, I can probably hack my way to build a firmware, but I don't want to "brick my brick" so I was hoping someone had done it and could give me some help...

I got nxt-python to work a few years ago, but it's buggy and slow, really want to get this to work!

[dlech]

It is currently possible to boot Pybricks on NXT, but there is still quite a bit of work to do to make if fully functional. If you want to try it, you can grab the latest build from CI , use a paper clip to press the hidden reset button on the NXT to put it in bootloader mode and flash it with pipx run pybricksdev flash nxt-firmware-build-2436.zip.

You don't need to worry about bricking the NXT. There is a permanent bootloader on the NXT, so even if you botch the firmware install, you can always activate the bootloader using the reset button on the NXT brick.

There is also an open issue for full support for NXT at #122.

Also, FYI, the Pybricks NxOS fork is now merged into https://github.com/pybricks/pybricks-micropython so we won't be updating https://github.com/pybricks/nxos anymore.

[laurensvalk]

Thank you Laurens. Just curious if I could help, but you know I am no programmer (not really).

@BertLindeman, you are super helpful as it is 😄 Look what I got the other day:

It was quite a challenge for the primary school students I teach to make the switch from Spike to Pybrics.
At a critical moment when we really didn't know how to proceed due to technical problems Bert Lindeman and David Lechner jumped in with the answer (on Github).

And then the great project that my students had just had to be implemented through the excellent Pybrics firmware.

The SILVER medal won the team I teach STEM........and the rest is history...

So thank you!

[BertLindeman]

Getting all warm.
Thank you for sharing this.
Will go back and retry the NXT as it is a fun device.
And try be not too talkative.

[laurensvalk]

I will try to push some updates some time soonish. It's possible that I'm building off an older branch and something broke more recently. I do see a potential issue in the latest build 😉

[BertLindeman]

No problem Laurens.

[BertLindeman]

Confirm getting the REPL flashing the oldest nxt firmware I have: nxt-firmware-build-3357-gitd3f38000.zip

Hello!
World!
Traceback (most recent call last):
  File "hello.py", line 8, in <module>
KeyboardInterrupt:
Pybricks MicroPython ci-build-3357-v3.5.0b1-12-gd3f38000 on 2024-04-04; LEGO MINDSTORMS NXT Brick with AT91SAM7S256
Type "help()" for more information.
>>>

For my memory:
Flash with pipx run pybricksdev nxt-firmware-build-3357-gitd3f38000.zip'
The device was already paired.
Setup serial interface: sudo rfcomm release /dev/rfcomm1 ; sudo rfcomm bind /dev/rfcomm1 00:16:53:0C:2E:97
get terminal: screen /dev/rfcomm1

FUN!

[skippa]

Excellent! Thanks for your reply, I'll have a go and see what it can do, then report back

…

On Sun., Feb. 5, 2023, 1:54 p.m. David Lechner ***@***.***> wrote: It is currently possible to boot Pybricks on NXT, but there is still quite a bit of work to do to make if fully functional. If you want to try it, you can grab the latest build from CI <https://github.com/pybricks/pybricks-micropython/suites/10745069382/artifacts/539132296>and flash it with pipx run pybricksdev flash nxt-firmware-build-2436.zip. You don't need to worry about bricking the NXT. There is a permanent bootloader on the NXT, so even if you botch the firmware install, you can always activate the bootloader using the reset button on the NXT brick. There is also an open issue for full support for NXT at #169 <#169>. — Reply to this email directly, view it on GitHub <#939 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABNABBC3JP6PQK6YQ7BA7MDWV4P57ANCNFSM6AAAAAAUROQ7NE> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[skippa]

Ok, so I was able to successfully install the firmware on my NXT. I could also pair the bluetooth device. However, I cannot connect to bluetooth in pybricks. I'm using Chrome and have enabled web bluetooth as per the instructions... Anything else I can try?

[laurensvalk]

That part of it is not implemented yet, and probably won't be for a while :)

But if you've paired with your computer, you should be able to open the virtual com port that is now available. On Linux, you could use screen, or Putty on Windows, for example.

[dlech]

Or https://googlechromelabs.github.io/serial-terminal on any OS.

[skippa]

Ah ok, I'll have a play How complicated is this to implement? Maybe I could assist...

…

On Mon., Feb. 6, 2023, 6:31 p.m. laurensvalk ***@***.***> wrote: That part of it is not implemented yet, and probably won't be for a while :) But if you've paired with your computer, you should be able to open the virtual com port that is now available. On Linux, you could use screen, or Putty on Windows, for example. — Reply to this email directly, view it on GitHub <#939 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABNABBD4YZMBDAGDBHFWY3DWWCZH3ANCNFSM6AAAAAAUROQ7NE> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[dlech]

1. The Pybricks Profile specification needs to be modified to allow all functionality over an RFCOMM socket.
   1. Instead of a separate NUS service, we need to add a new command and a new event to the Pybricks service for stdio.
   2. We also need a command(s) and event(s) for the Device Information Service.
   3. Since RFCOMM is essentially a stream of bytes, we will need to add a header containing the message size and sequence number to encapsulate Pybricks Service commands and events in the stream.
   4. We need a new event type that can act as the response to commands that are "write with response" in the GATT version of the protocol.
2. Alternately, we could do something that approximates GATT over RFCOMM.
   1. This would need the same size and sequence number header but also include a GATT command/event and attribute handle
   2. The reset of the message would contain the same data as the current Pybricks Profile dictates
3. One the protocol is worked out on paper, it needs to be implemented in the firmware, in pybricksdev and in Pybricks Code.

[skippa]

Any update or progress on this?

[dlech]

We have defined the Pybricks Profile over USB in pybricks/pybricks-micropython#208. It isn't quite finalized yet, but should be very close.

If you are still interested in helping, porting that to NXT would be a good place to start.