www.LanternChess.com

Pulsar Chess Engine for Computers and Mobile
Mike Adams

Pulsar Icon Update Apr 1st 2023. A good link that explains Pulsar is the Chess Programming Wiki   Also a good summary of the Pulsar Chess Engine history can be found on my reddit post for Pulsar turning 25 https://www.reddit.com/r/chess/comments/11t6zlr/pulsar_chess_engine_turns_25/.

Pulsar version 2009(Mac, Windows, and Linux) can play Chess and the variants Crazyhouse, Atomic, Giveaway, Suicide, Loser's, Three Checks, Chess960, Shatranj, 2King, as well as various setboard wilds. Version 2007(Windows and Linux) will play all but Shatranj and Chess960. The latest version supports analysis mode in Atomic, Loser's, Giveaway/Suicide, Crazyhouse, 3Checks and regular chess.

For Pulsar to play Atomic Chess with fics rules use the word fics as a program argument. This applies to older versions as well. pulsarscoop2 link below for more info.

lanternbugs at gmail Dot com

Pulsar in iOS and Mac App Store

There is also a free Mac and an iOS version for tablets and phones at https://itunes.apple.com/us/app/pulsar-chess-engine/id839640447?mt=8 - US App Store link. Levels of difficulty can be set within the app. It also plays regular chess and difficulty can be set for that too. The variants it plays are Chess960, Crazyhouse, Atomic, Three Checks, Giveaway(similar to FICS Suicide) and Loser's.

Pulsar on Android in Play Store

As of Jan 2019 a free Android version of Pulsar if anyone wants to play Crazyhouse, Atomic Chess, Loser's Chess, Three Checks, Chess960 or Giveaway(also known as Suicide) on Android as well as Chess. href=https://play.google.com/store/apps/details?id=com.lantern.michaeladams.pulsarchessengine We have a support page for the apps which also has piece rights stated.

Pulsar on Amazon Fire Tablets and Windows 11

https://www.amazon.com/Michael-R-Adams-Pulsar-Engine/dp/B09CG78ZLC/ is the link for fire tablets to download from the Amazon App Store or search in store. Pulsar is now on Windows 11 in the Amazon App Store on Windows for compatible devices.

Download Pulsar2009-9b

March 4 2017 - Linux binary

pulsar2009-9b-linux-64.zip A pulsar2009-9b release that runs on Linux. Compiled from same code as original pular2009-9b. Download includes the books. It's an exact copy of the Mac code and I've run it in the console as well as in Lantern Chess using Options / Load Winboard Engine in ICC Examine mode which will start it in analysis mode. It's compiled on a copy of Linux Mint i have on an older laptop so probably 2011/12 with gcc and -O3 optimization. Same licence applies as other pulsar2009-9b releases i.e. pulsar2009-9b-linux-64 comes "as is", without any guarantees, and using it is entirely at your own risk. It can be freely redistributed in unmodified form, alone or in combination with other software.

March 3 2017 - Mac binary

macconsolepulsar2009b-release.zip A pulsar2009-9b release that runs as a Mac program. Compiled from same code as original pular2009-9b with a few edits to make it compile on Mac. Download includes the books. I tested this binary with the Mac Xboard running a computer account a few days. Same licence applies as other pulsar2009-9b releases i.e. macconsolepulsar2009b-release comes "as is", without any guarantees, and using it is entirely at your own risk. It can be freely redistributed in unmodified form, alone or in combination with other software.

September 6 2009 - Windows

pulsar2009-9b.zip This is an executable only (that means download the pulsar2009-9a release package as well for the books in .txt files) and fixes a stalemate issue in blitz. no changes to wild programs though shatranj is now included in its variants. You can edit them to refelct the new engine name. this version of pulsar of pulsar is distributed with winboard in one of the packages.
License conditions:
Pulsar 2009-9b comes "as is", without any guarantees, and using it is entirely at your own risk. It can be freely redistributed in unmodified form, alone or in combination with other software.

additional: pulsar2009-9b is expected to work with the books from pulsar2009-9a-release package. the licence also applies to any packaging of pulsar2009-9a.exe or pulsar2009-9b.exe with any combination of books that are wanted to be included from the 9a package ( with teh name changed to 9b for the 9b package). The release is understood to be the executables, 9a or 9b, and any combination of the books or bat files, or none, which are optional.

Pulsar customization pages

To get some more info on how to customize pulsar see:
pulsarscoop2.html
pulsarscoop.html

June 21, 2009 - Windows

pulsar2009-9a-release.zip pulsar2009-9a-release.zip is under the same liscence ( that is everything in the zip, the exe the books) as pulsar2009-9b. i will restate it here ( posted september 6 2009)

liscence pulsar2009-9a

pulsar2009-9a-release.zip comes "as is", without any guarantees, and using it is entirely at your own risk. It can be freely redistributed in unmodified form, alone or in combination with other software,.

  This release plays normal chess, fischer random, shatranj, 3checks, atomic, crazyhouse, losers, 2kings, suicide/giveaway and shuffle chess all in one program. Also added analysis mode in atomic, losers, giveaway/suicide, crazyhouse, 3checks and regular chess.

I have created some bat files to handicap it at the various variants into 5 levels of difficulty. They are:


pulsar09-atomic-batfiles.zip
pulsar09-3check-batfiles.zip
pulsar09-crazyhouse-batfiles.zip
pulsar09-twokings-batfiles.zip
pulsar09-regular-chess-batfiles.zip

Just extract them into the winboard folder and you can click on one of them to run pulsar at that variant at that difficulty.

Older versions

License conditions:
All older versions come "as is", without any guarantees, and using it is entirely at your own risk. It can be freely redistributed in unmodified form, alone or in combination with other software.

June 14, 2007 pulsar2007-9a-release.zip   This version plays normal chess, 3checks, atomic, crazyhouse, losers, 2kings, suicide/giveaway and shuffle chess all in one program.

Update March 15, 2009 for windows: engine only. pulsar2007-9a-1.zip.  This is an update of the 9a program for those interested in running it on an ics. It fixes two bugs that only impact ics play. One is problems resuming games in atomic and the other is not always using its book.

Note on handicaping: you can handicap pulsar to only search a certain amount of plys in different variants and normal chess. You need to use a program argument. The program arguments are:

mxA-1 through mxA-5 for atomic searching to ply 1 through 5.
mxT-1 through mxT-5 for 3checks searching to ply 1 through 5.
mxC-1 through mxC-5 for crazyhouse searching to ply 1 through 5.
mxS-1 through mxS-5 for suicide ( like icc giveaway exept you cant castle) searching to ply 1 through 5.
mxL-1 through mxL-5 for losers searching to ply 1 through 5.
mxO-1 through mxO-5 for the chess variants ( includes regular chess, shuffle chess and 2kings) searching to ply 1 to through 5.

to enter a program argument type instead of: -fcp pulsar2007-9a.exe         instead type -fcp "pulsar2007-9a.exe mxA-3" for example to handicap it to play atomic to ply 3. If running on the icc you can use multiple handicaps all listed at once ( whats not handicapped will play at full strenght). For example: -fcp "pulsar2007-9a.exe mxA-3 mxO-3 mxT-4 mxC-2"

Linux Versions of Pulsar

You can download a 32 bit or 64 bit version of the current pulsar at pulsar2007-9b-linux-32.zip

pulsar2007-9b-linux-64.zip

I havent had a chance to test these much but the compile seemed to go fine. People who have tried it say it works fine. These linux links are just the executable. You can get the books from the Windows download.
License conditions:
Pulsar 2007-9b for Linux comes "as is", without any guarantees, and using it is entirely at your own risk. It can be freely redistributed in unmodified form, alone or in combination with other software.

to make pulsar use variants you need to use the xboard '-variant' argument when you start it. You can use both -variant and /variant in winboard. examples:
-variant atomic
-variant crazyhouse
-variant losers
-variant suicide
-variant 3checks
-variant twokings

Winboard/Xboard

Pulsar is a winboard protocol 2 compatible engine. It does not implement the full winboard 2 or winboard 1 protocol. Some features such as analyze mode are currently not available. This version has been tested in winboard and chess partner 5.2.

Winboard and Xboard can be downloaded at the Winboard Forum

Using Winboard

To run a winboard program at home to play against it you typically start winboard with a .bat file. This is just a text file you place your startup line for the program created in notepad or another text editor. Once you have done that save it for for example as runpulsar.bat.

To run pulsar at home put: winboard.exe -fcp "pulsarV2.01e.exe"

Click on it to run.

Pulsar2007 plays variants so if your running a variant in home play you need the -variant or /variant option and the variant name which is listed above in the linux download section. only -variant works in linux though. Example:
winboard.exe -fcp pulsar2007-9a.exe -variant atomic

For pulsar2007-9a, if you want to use program argmenmts, described onpulsarscoop2.html then put the program name with its arguments in quotes. example: winboard.exe -fcp "pulsar2007-9a.exe mxA-3" -variant atomic

To run pulsar on an ics you need some additional flags than just -fcp which stands for first chess program. You will need -zp to tell it to be in zippy mode or automated mode, -ics to tell it to be in internet mode as well as -icshelper and -icshost to tell it to use timestamp or timeseal and to tell it what host to connect to.

Example chessclub.com is a host.

Example:
Winboard.exe -zp -ics -icshost chessclub.com -icshelper timestamp.exe -fcp "pulsarV2.01e.exe"

Information on these and other flags can be found in the winboard help index or help contents.

Some History

Beating the Chess Program

I am just going to write briefly here some historical comments. My first real experience with computer chess was the chess board program fidelity excellence which i purchased for my birthday December 1987 [ see
thoughts on chess board computers. ]. I was 17. I played that program at level 1 and could beat it with clever rook mates. But I never could beat it at level 6 or higher.

In 1996 i returned to chess, got a bit better, and could finally beat it at all times under a minute per move. I had done some programming in the meantime. As of yet, I hold no degree in programming, but at the time I had made a arkanoid clone for dos called powerout which I distributed as shareware and a text editor. powerout 2.5 , a vbdos 1 game, and be sure to read the readme.txt for a few useful hints.

In 1997 I bought fritz 4 and in April of 1998 I joined the icc. Shortly thereafter I began to run a crafty account. I was new to internet chess and computer chess seemed like an exciting avenue to pursue. About 2 months after I started my crafty account I decided to write a chess program. This was october 1998.

With help from people on icc's channel 64 most notably kiwipete and diepeveen I got pulsar running on the icc in December and January of 1998/99. It was written in c. The early version did not have a qsearch. It had capture extensions. It only ordered moves by captures and killer moves at the start. Eventually hashing and null move were added and pulsar broke 2200 in the fall of 2000.

In the fall of 2002 I added wild capactiy to pulsar including atomic and 3checks. Atomic has evolved into its own independent program. Now in June 2003 pulsar has been released for the first time.