Can MATLAB Mobile on Android Access USB Serial Devices (Raspberry Pi Pico)?

Here's the hardware I'm working with:

• Kindle Fire Tablet (10" 2023 edition) with USB OTG support
• Raspberry Pi Pico (USB serial device)
• USB debugging enabled on Android via developer settings

My goal is to establish serial communication between MATLAB Mobile on Android (on my Kindle Fire tablet) and a Raspberry Pi Pico via USB connection for a university engineering project. The same code works perfectly on desktop MATLAB.

Here's what I've figured out:

• Desktop MATLAB on Windows successfully connects to the Pico using serialport()
• The Pico is powered when connected to the Kindle Fire (USB connection is functional)
• MATLAB Mobile accesses built-in Android sensors (accelerometer, camera, etc.)

My problem is that when running serialportlist on MATLAB Mobile, I only see built-in serial ports:

X = serialportlist;

disp(X)

Output: "/dev/ttyS2" "/dev/ttys0" "/dev/ttyS3" "/dev/ttyS1"

These are hardware UARTs on the Android device itself, not USB devices. When the Pico is properly detected via USB, I should see /dev/ttyACM0 or similar.

These are some extra issues I noticed.

• No USB notification appears when Pico is plugged in (unlike when plugging into PC)
• Attempting to connect gives: Unable to connect to the serialport device at port '/dev/ttyS1'
• Android terminal apps (Termux) cannot access /dev/ without root (I would be willing to root my device but would rather not)

Here are my questions:

1. Does MATLAB Mobile support USB serial communication at all? The documentation only mentions built-in sensors.
2. If it does support USB, are there special Android permissions or settings required?
3. Are there any workarounds or alternative approaches to connect external USB hardware to MATLAB Mobile?
4. Would network-based communication (TCP/UDP) be supported if I switched to a Raspberry Pi Pico W?

Any guidance would be greatly appreciated. If USB serial isn't supported, I need to know definitively so I can find something different before my project deadline.

Answer 1

[Satyam]

Hi Tucker,

No, MATLAB Mobile on Android cannot access USB Serial devices using a serial connection. MATLAB Mobile allows you to connect to a MATLAB session running in the MathWorks Cloud. The Serial Port interface is supported by the following platforms, https://www.mathworks.com/help/matlab/import_export/troubleshooting-serial-port-interface.html

Unfortunately, it is not supported in MathWorks Cloud. So, Serial Port interface cannot be used from the MATLAB mobile. If you need to get data from a USB serial device into MATLAB Mobile, you can try out the following steps:

1. Connect to a computer: Connect your USB serial device to a desktop computer running a full version of MATLAB.
2. Use TCP/IP or UDP: Create a network connection (via TCP/IP or UDP) on the desktop to stream the serial data to your Android device.
3. Use MATLAB Mobile: Use MATLAB Mobile on your Android device to receive and process the data over the network connection.

[Tucker]

Hi Satyam, thanks for your response.

I figured this was the case, so unfortunately, I will not be able to use MatLab for this project. Disappointing that this functionality is not built into all MatLab versions; maybe MathWorks will implement something similar in the future?

For others having similar issues to me, I ended up forgoing MatLab entirely and using a Python server running Flask to host a local website where UI/UX elements can be displayed. This way, the entire system can run solely on the tablet and the Pico with no need for an external laptop or desktop.