I need a way to make hardwired digital inputs available to Flow cards in a Homey Pro. The Raspberry Pi app from Robin de Gruijter says that 54 GPIO (0-53) can be addressed. Since the Raspberry Pi only has 26 GPIO pins, I suspect that the easiest way to gain more is to use an MCP23017 (which requires three of the 26 GPIO for addressing).
If I used two MCP23017s, would I really have 54 I/O available (23+16+15)? If not, how do I get the 54 I/O points supported by the app?
Thank you.
The RPi SoC has 54 GPIO pins on the chip, but not all of them are exposed through the GPIO connector. The others are either not used, or they are used internally, for things like the SD card interface, LED’s, audio, etc (see here).
In other words, you should limit yourself to the GPIO pins available through the connector.
Just to confirm - using one Raspberry Pi, the most external digital inputs I could bring into Flows is 26?
If that is the case, it looks like I’d have to use an Arduino and the Homeyduino app. Then I’d get about 54 points with an Arduino Due - right? Boy, I really didn’t want to deal with C/C++. Any other ideas? I need at least 48 total inputs.
Thanks, again.
Correct.
Searching for “ESPHome I/O expander”, you run into devices like this one, although I’m not sure if the ESPHome app for Homey supports them directly (but since ESPHome supports MQTT, and Homey does too, you could use that protocol for communication).
Thanks for confirming, Robert.
The KinCony part shown in your link sure has everything I am looking for. But at that cost and the programming involved, I think maybe two Raspberry Pis (or maybe two Zeros or two Picos) would be the route to take. Thank you for taking time to make a suggestion.
John Rex.
| robertklep
September 24 |
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John_Rex:
Just to confirm - using one Raspberry Pi, the most external digital inputs I could bring into Flows is 26?
Correct.
If that is the case, it looks like I’d have to use an Arduino and the Homeyduino app. Then I’d get about 54 points with an Arduino Due - right? Boy, I really didn’t want to deal with C/C++. Any other ideas? I need at least 48 total inputs.
Searching for “ESPHome I/O expander”, you run into devices like this one, although I’m not sure if the ESPHome app for Homey supports them directly (but since ESPHome supports MQTT, and Homey does too, you could use that protocol for communication).
