Setting up com0com with WSL and brickEmu

[Alexander207]

I'm trying to route a set of virtual COM ports from my Windows 98 virtual machine to brickEmu via com0com. I tried doing it many different ways but it isn't working.

How do I even use com0com to connect my Windows 98 VM with brickEmu on WSL2?

[mesheets]

A few questions—

1. Is ir-server running without issue?
2. What is the virtualization host platform? If Hyper-V, is it a Gen 1 or Gen 2 VM?
3. What firmware(s) are intended to be used with this brickEmu setup (standard Lego, brickOS, leJOS, etc.)?
4. What software (and versions) running on the Windows 98 VM would be connected to brickEmu?
5. Are there any technical restrictions that limit the OS in the VM to Windows 98 (Second Edition?), or if the desired software can be made to run on a different OS, might that also be acceptable?

In addition to brickEmu, there is also the Java-based RCXSimulator. While RCXSimulator offers some enticing features, unfortunately is it not as performant as brickEmu, the only source code that is available is what has been decompiled from the jar file, and the researcher who had been working on this is no longer with that university. Note that an RCX ROM image also needs to be provided for RCXSimulator, which is optional with brickEmu.

[Alexander207]

IR server seems to be running properly, but I get the "Unable to delete firmware" error message when I try to download firmware to RCXSimulator from the same instance of WSL (I'm using version 2).
Windows 98 is running on 86Box (Which is a fork of PCem).
I intend to use the standard LEGO firmware with this setup.
I'm trying to run the official Mindstorms Robotics Invention System software in Windows 98 First Edition.
I don't think there are technical restrictions that prevent other operating systems that are compatible with the software from running on 86Box, and I believe the same thing that I'm having now would still happen even if I was using Windows 98 or Windows Me

[mesheets]

With RCXSimulator, the original developer recommends using the "-f" option to preload firmware.

By my notes, the most recent version of Java supported on Windows 98 SE is 1.5.0.2 (a.k.a. 5.0 Update 22). A GDB stub was one of the later features added to RCXSimulator, and that only required Java 1.4. I don't know offhand where Java support for Windows 98 First Edition dropped off, but it might be possible to run RCXSimulator in the VM alongside the Robotics Invention System.

Also, LEGO did release a patch to fix an issue running RIS 2.0 under Windows XP and later (copy available here).

There are also two potential visual-based alternatives to the Robotics Invention System:

• VisualNQC - Java app that provides an icon-based programming experience. It generates NQC code, which in turn is compiled into programs that can be executed on Standard LEGO 2.0 firmware (as the 2.0 firmware is compatible with the 1.0 and 1.5 programmable bricks). Java GUI development at that time did not support touch or digitizer pens very well, but regular keyboard/mouse use as one might expect of the Windows 9x era shouldn't have any issues.
• WebPBrick - This is more something under development to keep an eye on, but this project strives to provide a browser based development environment for the RCX, including both with NQC code and visual icons. I've supported that project by enabling WebAssembly builds of NQC and also updating how the WebAssembly is loaded into the web page, so that the web page can be opened as a local file without needing to run from a web server. The icon and code editor functionality isn't linked yet, so after writing a program using BlockNQC, one has to generate the code there and then copy and paste it in the code editor page to generate the compiled NQC program.

If everything is running within the virtual machine itself, a basic installation of com0com with a single pair of linked serial ports should suffice. Connect one end of the serial pair to the programming software (Robotics Invention System, VisualNQC, etc.) and connect the other end to RCXSimulator using the -ir=PTY:COMx (where "x" is you COM port number) command line argument.

[Alexander207]

Where do I use the -ir option?

[mesheets]

At the moment, the full list of command-line arguments for RCXSimulator is still on the university website.

It would be something like:

java -jar RCXSimulator.jar -r ROM.srec -f firmware.srec -ir=PTY:COM1

[Alexander207]

But my brickOS files are on my WSL Ubuntu instance. I'm only using the Windows 98 machine to run the programming software.

[mesheets]

In working with GitHub user solsjo on brickEmu, the overflow error that was tripping up the pyTest step when running on Ubuntu 24.04 appears to have been resolved.

If you do use RCXSimulator more, I would be interested to hear how your experience with it goes, especially how the performance feels for you.

[Alexander207]

It's really slow, and it ticks me off to the point where I would probably just stick with brickEmu. I also want to have brickEmu send outgoing data to a serial port on my Ubuntu VM, which I'm running in VirtualBox, but I'm not sure if it's possible.

[mesheets]

ir-server basically enables the serial communication to happen over TCP/IP. Using the socat command on Linux or one of the utilities included with com0com, it is possible to translate between the serial communication and TCP/IP.

Newer builds of firmdl, dll, lnpmsg, and even the Linux version of NQC have had additional support added so that they can also now communicate directly over TCP/IP.

There is also a version of ir-server in the brickOS-bibo project. Unlike ir-server in brickEmu, it is not currently configured to run as a service, but it does include the same additional command-line options that enable it to connect to a serial port or USB IR tower and include that device in its communication loop.

Those capabilities even makes it possible to communicate remotely over the internet with an RCX, or enable a virtual RCX to communicate with a real RCX.

[Alexander207]

Can ir-server emulate an IR tower?

Also, I keep trying to download the official LEGO firmware using firmware dl but I get this error:

Cannot conect to config: Conection refused

[mesheets]

Can ir-server emulate an IR tower?

It doesn't really emulate an IR tower, per se; just like additional command-line options were added when USB towers came along, additional command-line options have also been added to support TCP. For software (such as that from LEGO) which never built in TCP support, other tools like com0com (Windows) or socat (Linux) are needed to either (1) create a translation layer between a serial port (like LEGO's software understands) and TCP or (2) create a virtual serial port bridge so that the non-TCP supporting software can connect to the virtual serial port on one end and the ir-server from the BrickOS-Bibo project can connect to the virtual serial port on the other end. The same digital bits are communicated regardless of whether a serial, USB, or TCP communication mechanism is specified. It is more of its own entity that is capable of multiple things:

• An extender that facilitates communicating with a remote RCX (either physical [via an IR tower] or virtual)
• A node to which virtual RCX devices can connect
• A virtualizer of IR communication's broadcast effect, such as would happen when multiple RCX units and/or IR towers are in a room.
  • If using the virtual remote, its messages will be sent to all RCX units (physical or virtual) connected to a given ir-server.
  • Even though they might each be in their own location, multiple RCX units connected via a given IR server can communicate with each other.

With both brickEmu and RCXSimulator, use of the respective command line argument to sideload the firmware is recommended. The brickEmu user interface even includes a menu option for sideloading firmware the point-and-click way.