interfacing an emulator

I was curious what the elo rating of UltraChess is.
UltraChess is a chess program running on old 8-bit Z80 based MSX hardware.
UltraChess requires someone to enter the moves manually on the keyboard of the MSX. It will then display the result on the screen. It has (had) no way of interfacing to an other chess program.

Enter OpenMSX. OpenMSX is an MSX emulator.
OpenMSX has a scripting interface. Using TCL scripts you can press keys on the virtual keyboard, switch the device on and off, peak in the memory, and so on.

The scripting of OpenMSX allowed me to create a Python script that starts a chess game on the emulated MSX and let it talk to an other chess program (if it can talk UCI). The result is a PGN-file that then can be processed using Bayes-Elo to calculate the ELO ratings.

try it

The script is on GitHub.

You may whish to make a couple of changes before running it:


This is an example of UltraChess playing against an other program (Shallow-blue in this case). On you can read an analysis of it. Below you can view the game.

elo rating

I don't know...yet!
The problem is that UltraChess is apparently so weak that it only loses from all the (UCI) chess programs I let it play against. To be able to calculate the elo rating, it should at least occasionally win or at least play draw.

For contact info, see this page.

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