Free Serial Terminal Windows 10

I hope that this blog post is found and helps someone. I wasn't sure what to title it. Hope Google Juice got you here! Read this whole post, there's a lot initially but there's really just two or three small pieces.

It'll be worth it because you'll be able to have a nice one click menu and drop directly into a serial port terminal on Windows in the Windows Terminal. Often when you're doing embedded systems development you'll want to monitor or talk to the COM/Serial Port just like you SSH into remote system.

Ensure dialout permissions to talk to the COM port

Folks ask questions like "How to connect to a serial port as simple as using SSH?" On Linux you'll use things like "screen /dev/ttyS0" for COM0. With Windows, however, the historical guidance has always been to use Putty. It'll work but it's somewhat old, quirky, and it doesn't integrate well with the Windows Terminal and a more modern workflow.

Say I have a small embedded microcontroller device that talks over a COM Port (usually via a USB->COM bridge) like an Arduino. Let's assume this device talks to the COM port as if it were a terminal and it's outputting stuff I want to see.

Setup WSL1

I'll use this great little CLI example app for Arduino from Mads Aasvik to simulate such a device. Here's what it looks like under Arduino's Serial Monitor, for example. This is a Windows app doing serial communication with its own interface wrapping around it.

I want to do this at a command line, and bonus points if it's in Windows Terminal. If you have Windows 10 you can the Windows Subsystem for Linux quickly with this command at a Admin prompt:. Then go to the Windows Store and get any small Linux. Ubuntu or Kali will do for our purposes.

Run it and set your user and password. (I tried Alpine but it still has issues with screen and /dev/null/utmp).

Get Minicom on your WSL1 distro

NOTE: If you are using WSL2 and have set it as default, run wsl --list -v and ensure that your new distro is using WSL1 as only WSL1 will let us talk to the COM Ports. You can change it to WSL1 with "wsl --set-version DISTRONAME 1" from any command prompt.

To test this out now, run your new distro from any command line prompt like this. Add the "screen" app with sudo apt update" and "sudo app install screen". You can see here that my Arduino serial device is on COM4.

On Linux that device is /dev/ttyS4 . That means that I should be able to talk it from any WSL1 Linux Distro on Windows like "screen /dev/ttyS4 9600" where 9600 is the speed/baud rate. Screen is somewhat persnickety for Serial Port work so try Minicom. Minicom is a nice little text com program. Install with apt install minicom and run for the first time with "sudo minicom -s" to set your default.

Make a nice menu

Note I've change the default port from /dev/modem to /dev/ttyS4 and the speed, in my case, to 9600. Then I hit enter and save settings as the dft (default) in minicom. You can also turn on Local Echo with "Ctrl-A E" and toggle it if needed. Now I can talk to my Arudino with minicom.

NOTE: If you get "cannon open /dev/ttyS4: Permission denied, you may need to add your user to the dialout group. This way we don't need to sudo and get no prompt when running minicom!

I can now run minicom on my configured COM port 4 (/dev/ttyS4) with wsl -d DISTRONAME minicom without sudo. Here I'm talking to that Arduino program. This embedded app doesn't need to me hit enter after I type, so remember your own embedded devices will vary.

Bonus points, now I'll add a menu item for Minicom by changing my Windows Terminal settings AND I'll get more points for adding a nice serial port icon! I hit settings and add a new profile like this at the top under profiles in the "list."

KiTTY

Again, your distro name will be different. Use a WSL1 distro . Install minicom, run with minicom -s once to make settings Make sure you are using the right /dev/ttyS0 device for your situation Ensure your flow control, baud, etc are all correct in minicom Add your user to the dialout group so you don't have to sudo minicom.

Make sure you are using the right /dev/ttyS0 device for your situation . Ensure your flow control, baud, etc are all correct in minicom .

Add your user to the dialout group so you don't have to sudo minicom. Make a menu item in Windows Terminal or run minicom manually in your WSL1 instance whenever you like. or run minicom manually in your WSL1 instance whenever you like. Hope this helps! Sponsor: Suffering from a lack of clarity around software bugs?

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SmarTTY

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee.

He is a failed stand-up comic, a cornrower, and a book author.

If that doesn’t bother you, then SmarTTY offers a very cool multi-tab, graphical SSH tool and is also perfectly capable of serial port functions and Telnet.

Are You Out There?

Apart from how useful a terminal emulator program can be, there’s something wonderfully nostalgic about staring at the infinite blackness of a terminal, with its lone blinking cursor. While it’s never possible to go back in time, we can at least pretend that those heady early days of computing are still with us. Just like the hacker elite we imagine we are.

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