Remote control 51515 from a Windows application

[brabebhin]

Hello,

I have been looking into ways to remove control the 51515 set hub from a Windows application. The Windows application should preferably connect to the hub via bluetooth, read some sensor data, and based on the sensor data, compute what to do next. The possible commands would be to continue to move forward at a computed speed,or stop.

The Windows application is preferably written in C++ as it needs access to some very low hardware functions on the host machine. If possible I could split the application that connects to the hub from the one that computes the speeds through some RPC. The important part is being able to send commands to the hub and get responses in real time.

Is this scenario possible with pybricks?
If it is not possible with 51515 hub, is it possible with other hubs that are currently available on the market?

Thanks.

[brabebhin]

Buried deep into the interwebs I found this

#154

Seems to be what I need.
I will be back if I can't get it working.

[laurensvalk]

New lines become available in hub.output when a new line is received.

This would be every time you print a line using print() or sooner if you send the end of line symbol \r\n explicitly.

[brabebhin]

Hi @laurensvalk

Thanks for the prompt response!

You mean using the "print" function in the hub (physical hub)? There still seems to be some delay. Is there another way to read stuff from the hub? Like reading from a GATT characteristics or something?

Thanks.

[laurensvalk]

Yes, that's the one.

The class you are using looks like this: https://github.com/pybricks/pybricksdev/blob/master/pybricksdev/connections.py#L150

Perhaps you can modify it to suit what you are trying to do.

[laurensvalk]

It looks like you are using a blocking sleep call. This causes everything else to block for 5 seconds. Is this the delay you are seeing?

You'll want to replace it with

await asyncio.sleep(5)

[brabebhin]

You are completely right. Now it seems to update in a timely manner. I completely missed the async stuff.
Thanks!

[lobodpav]

Tried the Keyboard remote control and it works fine in https://code.pybricks.com

When trying pybricksdev, it doesn't. I recall pybricksdev not supporting sending commands back to the hub from some other discussion.

I was wondering, would there be any way to run a program on the Hub and connect it to, say PlayStation gamepad?

Asking because currently when I want BT remote control, I use Lego FW. When I need an autonomous robot, I re-flash Pybricks. This is very inconvenient and I'd like to use pybricks only if possible, and ideally without the need for a computer. I.e. the Hub and a remote controller only.

[dlech]

When trying pybricksdev, it doesn't. I recall pybricksdev not supporting sending commands back to the hub from some other discussion.

pybricks/pybricksdev#17

I was wondering, would there be any way to run a program on the Hub and connect it to, say PlayStation gamepad?

#191