Y-cable on GPIO port from xBuddy, possible?
Hi,
Regarding one project to use, I need to use GPIO port from xBuddy to it, but I have already GPIO Hackerboard. Is it possible to create Y-cable to have one input and to outputs? Meaning that I will have one connector from xBuddy and two connectors - one for GPIO Hackerboard and one for the other project, which acts like GPIO Hackerboard too. Could it be done like this? I understand, that I will still have 0-7 pins to use, it will be just doubled (basically two outputs, one on each end), the goal is to be able to still use certain pins from Hackerboard, which are not available on the other projects
I would really appreciate any feedback on this 🙂
RE: Y-cable on GPIO port from xBuddy, possible?
I don't see why not. The port on the xBuddy that the GPIO plugs into is just an I2C port which can have multiple things on it. I2C signaling starts with an address and then a command. Only devices that are configured to the address should pay attention to the command, and you should only have one device per address to avoid collisions. Star topologies aren't exactly common for I2C, but with the proper resistor terminations I don't see why it shouldn't work as long as you don't get carried away.
Now, if you are talking about connecting two hacker boards to the same port on the xBuddy that probably won't work because the hackerboards are all hardcoded to the same I2C address. And even if you were able to change the address of one of the hackerboards, the default Prusa firmware wouldn't attempt to speak to it because it wouldn't know about the second address.
See my (limited) designs on:
Printables - https://www.printables.com/@Sembazuru
Thingiverse - https://www.thingiverse.com/Sembazuru/designs
RE: Y-cable on GPIO port from xBuddy, possible?
Thank you very much for your quick and helpful response. If the other device is just "passive" and only reading the LOW/HIGH state, does it mean, that it should work without any issue?
Is it better to use one-way diode on both ends or not needed?
In worst case it will not work, nothing will be damaged I guess, right?
RE: Y-cable on GPIO port from xBuddy, possible?
Thank you very much for your quick and helpful response. If the other device is just "passive" and only reading the LOW/HIGH state, does it mean, that it should work without any issue?
Is it better to use one-way diode on both ends or not needed?
In worst case it will not work, nothing will be damaged I guess, right?
Either I don't understand what you are trying to accomplish, or you don't know the difference between GPIO and I2C. Very simply, I2C is a messaging protocol, kind of similar to a language (English, French, Croatian, Python, etc). GPIO is generally just highs and lows, kind of like Morse Code. If something is expecting Morse Code and hears something speaking in a complex language it won't understand it. Similarly (like me) I expect English words and phrases and if I hear Morse Code I won't understand it. (Yeah, I don't know Morse Code.)
See my (limited) designs on:
Printables - https://www.printables.com/@Sembazuru
Thingiverse - https://www.thingiverse.com/Sembazuru/designs