I'm designing my next project, and was wondering if it's possible to access GPIO on an Android tablet. I know you can do this on a PC using a breakout board like the Adafruit FT232H. Is there something similar I can use with an Android tablet?
I'm designing my next project, and was wondering if it's possible to access GPIO on an Android tablet. I know you can do this on a PC using a breakout board like the Adafruit FT232H. Is there something similar I can use with an Android tablet?
You can; many USB UART chips have spare GPIO, you usually need Android software from the manufacturer to support it.
For example, if you use a USB UART chip from Cypress/Infineon, then the Android SDK is downloadable here:
However, if you're a beginner with Android, personally I would simply use USB serial, or WiFi or Bluetooth, to (say) a Pi Pico, and control the GPIO from that. The reason is, it is very easy to (say) use the network or Bluetooth from many programming languages, whatever you're familiar with, so that you don't need to work low-level with an SDK.
Example: it's easy to control things using BLE, using a web page (which works with not just Android, but also iPhones etc, Linux, Windows, etc.. not restricted to Android.
If you're a beginner, I'd suggest investigating how to use a Pi Pico, and then control that from your tablet, using the interface of your choice (USB serial, WiFi or BLE, if you use the Pico-W variant).
There are many solutions for USB OTG I/O
Check out IOIO OTG for android
If the Android tablet USB port supports OTG functionality then it will act as a USB host to potentially allow you to connect to other peripherals like the Adafruit FT232H.
If your tablet has a micro USB connector then this Adafruit OTG host cable may help you too.
https://www.adafruit.com/product/1099
If you search on Amazon or equivalent you should also find OTG USB C connector cables.