Path: bloom-beacon.mit.edu!senator-bedfellow.mit.edu!faqserv From: stst@vuse.vanderbilt.edu (Stefan Strack) Newsgroups: rec.games.corewar,rec.answers,news.answers Subject: Core War Frequently Asked Questions (rec.games.corewar FAQ) Supersedes: Followup-To: rec.games.corewar Date: 6 Apr 1994 11:13:06 GMT Organization: The Core War Newsletter Lines: 593 Approved: news-answers-request@MIT.Edu Expires: 5 May 1994 11:12:37 GMT Message-ID: Reply-To: stst@vuse.vanderbilt.edu (Stefan Strack) NNTP-Posting-Host: bloom-picayune.mit.edu Summary: This posting contains a list of Frequently Asked Questions (and their answers) about the game Core War. It should be read by anyone interested in posting to the rec.games.corewar newsgroup or submitting warriors to the ongoing Core War tournament - KotH. X-Last-Updated: 1994/01/10 Originator: faqserv@bloom-picayune.MIT.EDU Xref: bloom-beacon.mit.edu rec.games.corewar:1333 rec.answers:4776 news.answers:17730 Archive-name: games/corewar-faq Last-modified: 1994/01/03 Version: 2.1.5 These are the Frequently Asked Questions (and answers) from the USENET newsgroup rec.games.corewar. This FAQ list is also available by anonymous FTP from rtfm.mit.edu as pub/usenet/news.answers/games/corewar-faq.Z. TABLE OF CONTENTS Line ------------------------------------------------------------------------ 1. What is Core War? 69 2. Is it Core War or Core Wars? 82 3. Where can I find more information about Core War? 90 4. Core War has changed since Dewdney's articles. Where do I get 108 a copy of the current instruction set? 5. What is this ICWS'94? 122 6. What is the ICWS? 138 7. What is TCWN? 148 8. How do I join? 156 9. Are back issues of TCWNs available? 173 10. What is the EBS? 180 11. Where are the Core War archives? 196 12. Where can I find a Core War system for . . . ? 214 13. I do not have ftp. How do I get all of this great stuff? 262 14. I do not have access to Usenet. How do I post and receive news? 269 15. When is the next tournament? 287 16. What is KOTH? How do I enter? 296 17. Is it DAT 0, 0 or DAT #0, #0? How do I compare to core? 440 18. How does SLT (Skip if Less Than) work? 452 19. What does (expression or term of your choice) mean? 464 20. Other questions? 592 --------------------------------------------------------------------- Q 1: What is Core War? A 1: Core War is a game played by two or more programs (and vicariously by their authors) written in an assembly language called Redcode and run in a virtual computer called MARS (for Memory Array Redcode Simulator). The object of the game is to cause all of the opposing programs to terminate, leaving your program in sole posession of the machine. There are Core War systems available for most computer platforms. Redcode has been standardized by the ICWS, and is therefore transportable between all standard Core War systems. ---------------------------------------------------------------------- Q 2: Is it "Core War" or "Core Wars"? A 2: Both terms are used. Early references were to Core War. Later references seem to use Core Wars. I prefer "Core War" to refer to the game in general, "core wars" to refer to more than one specific battle. ---------------------------------------------------------------------- Q 3: Where can I find more information about Core War? A 3: Core War was first described in the "Core War Guidelines" of March, 1984 by D. G. Jones and A. K. Dewdney of the Department of Computer Science at The University of Western Ontario (Canada). Dewdney wrote several "Computer Recreations" articles in "Scientific American" which discussed Core War, starting with the May 1984 article. Those articles are contained in an anthology: Author: Dewdney, A. K. Title: The Armchair Universe: An Exploration of Computer Worlds Published: New York: W. H. Freeman (c) 1988 ISBN: 0-7167-1939-8 Library of Congress Call Number: QA76.6 .D517 1988 The Redcode language has changed somewhat since; see Q 4. --------------------------------------------------------------------- Q 4: Core War has changed since Dewdney's articles. Where do I get a copy of the current instruction set? A 4: A draft of the official standard (ICWS'88) is available by anonymous FTP from the Core War archives (soda.berkeley.edu) as pub/corewar/documents/standards/redcode-icws-88.Z This document is formatted awkwardly and contains ambiguous statements. For a more approachable intro to Redcode, take a look at pub/corewar/documents/tutorial.1.Z tutorial.2.Z (See also Q11) --------------------------------------------------------------------- Q 5: What is this ICWS'94? A 5: There is an ongoing discussion about future enhancements to the Redcode language. A proposed new standard, dubbed ICWS'94, is currently being evaluated. A major change is the addition of "instruction modifiers" that allow instructions to modify A-field, B-field or both. Also new is a post-increment indirect addressing mode and unrestricted opcode and addressing mode combination ("no illegal instructions"). ICWS'94 is backwards compatible; i.e. ICWS'88 warriors will run correctly on an ICWS'94 system. Take a look at the ICWS'94 draft for more information (soda.berkeley.edu pub/corewar/documents/icws94.draft.Z). You can try out the new standard by submitting warriors to the experimental '94 KotH server (see Q16). pMARS, a corewar system that implements ICWS'94 is available at soda (see Q12). --------------------------------------------------------------------- Q 6: What is the ICWS? A 6: About one year after Core War first appeared in Sci-Am, the "International Core War Society" (ICWS) was established. Since that time, the ICWS has been responsible for the creation and maintenance of Core War standards and the running of Core War tournaments. There have been six annual tournaments and two standards (ICWS'86 and ICWS'88). --------------------------------------------------------------------- Q 7: What is TCWN? A 7: Since March of 1987, "The Core War Newsletter" (TCWN) has been the official newsletter of the ICWS. It is published quarterly and recent issues are also available as Encapsulated PostScript on soda.berkeley.edu (see Q9). --------------------------------------------------------------------- Q 8: How do I join? A 8: For more information about joining the ICWS (which includes a subscription to TCWN), or to contribute an article, review, cartoon, letter, joke, rumor, etc. to TCWN, please contact: Jon Newman 13824 NE 87th Street Redmond, WA 98052-1959 email: jonn@microsoft.com (Note: Microsoft has NO affiliation with Core War. Jon Newman just happens to work there, and we want to keep it that way!) Current annual dues are $15.00 in US currency. ---------------------------------------------------------------------- Q 9: Are back issues of TCWN available? A 9: Recent issues can be found on soda.berkeley.edu (see Q11). Older issues (up to Winter 1991) are also available (see the next TCWN for details). --------------------------------------------------------------------- Q10: What is the EBS? A10: The Electronic Branch Section (EBS) of the ICWS is a group of Core War enthusiasts with access to electronic mail. There are no fees associated with being a member of the EBS, and members do reap some of the benefits of full ICWS membership without the expense. For instance, the ten best warriors submitted to the EBS tournament are entered into the annual ICWS tournament. All EBS business is conducted in the rec.games.corewar newsgroup. The current goal of the EBS is to be at the forefront of Core War by writing and implementing new standards and test suites in preparation for the tenth anniversary of Core War in May of 1994 (see Q 5). Its immediate business will be to set up a Charter and establish its officers. ---------------------------------------------------------------------- A11: Where is the Core War archive? Q11: Many documents such as the guidelines and the ICWS standards along with previous tournament Redcode entries and complete Core War systems are available via anonymous ftp from soda.berkeley.edu (128.32.149.19) in the /pub/corewar directories. Also, most of past rec.games.corewar postings (including Redcode source listings) are archived there. Jon Blow (blojo@soda.berkeley.edu) is the archive administrator. When uploading to /pub/corewar/incoming, ask Jon to move your upload to the appropriate directory and announce it on the net. Much of what is available on soda is also available on the German archive at iraun1.ira.uka.de (129.13.10.90) in the /pub/X11/corewars directory. This FAQ is automatically archived by news.answers. See the header for the current archive name and news.answers for how to get it. ---------------------------------------------------------------------- Q12: Where can I find a Core War system for . . . ? A12: Core War systems are available via anonymous ftp from soda.berkeley.edu in the pub/corewar/systems directory. Currently, there are Unix X-Window, IBM PC-compatible (sorry, no systems specifically designed for MS-Windows yet), Macintosh, and Amiga Core War systems available there. CAUTION! There are many, many Core War systems available which are NOT ICWS'88 (or even ICWS'86) compatible available at various archive sites other than soda.berkeley.edu. Generally, the older the program - the less likely it will be ICWS compatible. Reviews of Core War systems would be greatly appreciated in the newsgroup and in the newsletter. Below is a not necessarily complete or up-to-date list of what's available at soda: MADgic41.lzh - corewar for the Amiga, v4.1 MAD4041.lzh - older version? MAD50B.lha - corewar for the Amiga, beta version 5.0 Redcoder-10.hqx - corewar for the Mac core-11.hqx - corewar for the Mac core-wars-simulator.hqx - same as core-11.hqx? corewar_unix_x11.tar.Z - corewar for UNIX/X-windows, ICWS'86 but not ICWS'88 compatible koth31.tar.Z - corewar for UNIX/X-windows. This program runs the KotH server at intel.com koth.shar.Z - older version kothpc.zip - port of older version of KotH to the PC deluxe20c.tar.Z - corewar for UNIX (X-windows or curses) and PC mars.tar.Z - corewar for UNIX, likely not ICWS'88 compatible icons.zip - corewar icons for MS-Windows macrored.zip - a redcode macro-preprocessor (PC) c88v49.zip - PC corewar, textmode display mars88.zip - PC corewar, graphics mode display corwp302.zip - PC corewar, textmode display, slowish mercury2.zip - PC corewar written in assembly, fast! mtourn11.zip - tournament scheduler for mercury (req. 4DOS) pmars03s.zip - portable system, ICWS'88 and '94, runs on UNIX, PC, Mac, Amiga. C source archive pmars03s.tar.Z - same as above pmars03.zip - PC executables, graphics display version macpmars02.sit.hqx - pMARS executable for Mac ApMARS03.lha - pMARS executable for Amiga ---------------------------------------------------------------------- Q13: I do not have ftp. How do I get all of this great stuff? A13: There is an ftp email server at ftpmail@decwrl.dec.com. Send email with a subject and body text of "help" (without the quotes) for more information on its usage. ---------------------------------------------------------------------- Q14: I do not have access to Usenet. How do I post and receive news? A14: To receive rec.games.corewar articles by email, join the COREWAR-L list run on the Stormking.Com ListProcessor. To join, send: SUB COREWAR-L FirstName LastName to: LISTPROC@STORMKING.COM You can send mail to corewar-l@stormking.com to post even if you are not a member of the list. Responsible for the listserver is Scott J. Ellentuch (tuc@stormking.com). Another server that allows you to post (but not receive) articles is available. Email your post to rec-games-corewar@cs.utexas.edu and it will be automatically posted for you. ---------------------------------------------------------------------- Q15: When is the next tournament? A15: The ICWS holds an annual tournament. Traditionally, the deadline for entering is the 15th of December. The EBS usually holds a preliminary tournament around the 15th of November and sends the top finishers on to the ICWS tournament. ---------------------------------------------------------------------- Q16: What is KOTH? How do I enter? A16: King Of The Hill (KOTH) is an ongoing Core War tournament available to anyone with email provided by William Shubert (wms@iwarp.intel.com). You enter by submitting via email a Redcode program with special comment lines. You will receive a reply indicating how well your program did against the current top twenty programs "on the hill". Your program will play 100 battles against each of the 20 other programs currently on the Hill. You receive 3 points for each win and 1 point for each tie. (The existing programs do not replay each other, but their previous battles are recalled.) All scores are updated to reflect your battles and all 21 programs are ranked from high to low. If you are number 21 you are pushed off the Hill, if you are higher than 21 someone else is pushed off. Entry rules for King of the Hill Corewar: 1) Write a corewar program. KotH is fully ICWS '88 compatible, EXCEPT that a comma (",") is required between two arguments. 2) Put the line ";redcode" at the top of your program. This MUST be the first line. Anything before it will be lost. If you wish to receive mail on every new entrant, use ";redcode verbose". Otherwise you will only receive mail if a challenger makes it onto the hill. Use ";redcode quiet" if you wish to receive mail only when you get shoved off the hill. (Also, see 5 below). Additionally, adding ";name " and ";author " will be helpful in the performance reports. Do NOT have a line beginning with ";address" in your code; this will confuse the mail daemon and you won't get mail back. In addition, it would be nice if you have lines beginning with ";strategy" that describe the algorithm you use. 3) Mail this file to "wms@iwarp.intel.com". 4) Within a few minutes you should get mail back telling you whether your program assembled correctly or not. If it did assemble correctly, sit back and wait; if not, make the change required and re-submit. 5) In an hour or so you should get more mail telling you how your program performed against the current top 20 programs. If no news arrives in an hour, don't worry; entries are put in a queue and run through the tournament one at a time. A backlog may develop. Be patient. If your program makes it onto the hill, you will get mail every time a new program makes it onto the hill. If this is too much mail, you can use ";redcode quiet" when you first mail in your program; then you will only get mail when you make it on the top 20 list or when you are knocked off. Using ";redcode verbose" will give you even more mail; here you get mail every time a new challenger arrives, even if they don't make it onto the top 20 list. Often programmers want to try out slight variations in their programs. If you already have a program named "foo V1.0" on the hill, adding the line ";kill foo" to a new program will automatically bump foo 1.0 off the hill. Just ";kill" will remove all of your programs when you submit the new one. MORE ON KOTH COREWAR IMPLEMENTATION Core size: 8000 instructions Max processes: 8000 per program Duration: After 80,000 cycles, a tie is declared. Max entry length: 100 instructions Programs are guaranteed a 100 instruction block (inclusive of their warrior's instructions) without overlapping their opponent. SAMPLE ENTRY: ;redcode ;name Dwarf ;author A. K. Dewdney ;strategy Throw DAT bombs around memory, hitting every 4th memory cell. ;strategy This program was presented in the first Corewar article. bomb DAT #0 dwarf ADD #4, bomb MOV bomb, @bomb JMP dwarf END dwarf ; Programs start at the first line unless ; an "END start" pseudo-op appears to indicate ; the first logical instruction. Also, nothing ; after the END instruction will be assembled. Rule variants for "eXperimental" corewar: The same as above but use ";redcode-x" to start your program. Your program will be entered into a second tournament with slightly different rules. The rules are: - All addressing modes are allowed with all instructions. - There is an additional addressing mode, called "postincrement". To use it try an instruction like "mov >5,6". - The maximum write distance is 250 instructions. That is, every time your program tries to modify memory, the address is checked; if it is more than 250 instructions from the process doing the modify, then memory is left unchanged, but the instruction continues as normal. - A tie is not declared until 150,000 cycles per program have elapsed. KotH runs on any Unix system with an X windows interface. The source code to KotH is available by email from William Shubert. Write to him at (wms@iwarp.intel.com) for a copy or get it by anonymous FTP from soda.berkeley.edu in the pub/corewar/systems directory (see Q12). STORMKING.COM KOTH: A second KotH server is installed at stormking.com. Send your warrior to koth@stormking.com. Since this is an UUCP site, it may take a day before you get results back. There are currently five separate hills that you can select by starting your program with ;redcode, ;redcode-x ;redcode-icws, ;redcode-94, or ;redcode-94x. ;redcode and ;redcode-x select hills with rules of the regular and experimental hills at intel.com (see above). ;redcode-icws sends your warrior to the ICWS-hill. Rules here follow that of the annual ICWS tournament, in short: Core size: 8192 instructions Max processes: 64 per program Duration: After 100,000 cycles, a tie is declared. Max entry length: 300 instructions ;redcode-94 selects the experimental ICWS'94 (see Q 5 for more on this proposed new standard). Core size, Max processes, etc. are identical to the regular hills at stormking and intel.com. ;redcode-94x selects the experimental '94 or simply "Big Hill". Here the core size is 55440, a number with many small factors, that might lead to more complex warriors. Like the '94 hill, the '94x hill supports the ICWS'94 dialect. Here all parameters: Core size: 55,440 instructions Max processes: 10,000 per program Duration: After 500,000 cycles, a tie is declared. Max entry length: 200 instructions All hills at stormking.com except for the x-hill run portable MARS, a platform-independent corewar system available at soda (see Q12). The contact person is for this server is Scott J. Ellentuch (tuc@stormking.com). Please send all bug reports, inquiries, etc. to him and me (stst@vuse.vanderbilt.edu). ---------------------------------------------------------------------- Q17: Is it DAT 0, 0 or DAT #0, #0? How do I compare to core? A17: Core is initialized to DAT 0, 0. This is an "illegal" instruction under ICWS'88 rules and strictly compliant assemblers (such as KotH) will not let you write a DAT 0, 0 instruction - only DAT #0, #0. So this begs the question, how to compare something to see if it is empty core. The answer is, most likely the instruction before your first instruction and the instruction after your last instruction are both DAT 0, 0. You can use them, or any other likely unmodified instructions, for comparison. ---------------------------------------------------------------------- Q18: How does SLT (Skip if Less Than) work? A18: SLT gives some people trouble because of the way modular arithmetic works. It is important to note that all negative numbers are converted to positive numbers before a battles begins. Example: (-1) becomes (M - 1) where M is the memory size. Once you realize that all numbers are treated as positive, it is clear what is meant by "less than". It should also be clear that no number is less than zero. ---------------------------------------------------------------------- Q19: What does (expression or term of your choice) mean? A19: Here is a selected glossary of terms. If you have a definition and/or term you wish to see here, please send it to me. (References to an X-like program mean that the term X is derived from the specific program X and has become a generic term). Bootstrapping - Strategy of copying the active portion of the program away from the initial location, leaving a decoy behind and making the relocated program as small as possible. B-Scanners - Scanners which only recognize non-zero B-fields. example add #10,scan scan jmz example,10 C - Measure of speed, equal to one location per cycle. Speed of light. CMP-Scanner - A Scanner which uses a CMP instruction to look for opponents. example add step,scan scan cmp 10,30 jmp attack jmp example step dat #20,#20 Color - Property of bombs making them visible to scanners, causing them to attack useless locations, thus slowing them down. example dat #100 Core-Clear - code that sequentially overwrites core with DAT instructions; usually the last part of a program. Decoys - Bogus or unused instructions meant to slow down Scanners. Typically, DATs with non-zero B-fields. DJN-Stream (also DJN-Train) - Using a DJN command to rapidly decrement core locations. example . . . . . . djn example,<4000 Dwarf - the prototypical small bomber. Imp - Program which only uses the MOV instruction. example MOV 0, 1 or example MOV 0, 2 MOV 0, 2 Imp-Gate - A location in core which is bombed or decremented continuously so that an Imp can not pass. Also used to describe the program-code which maintains the gate. example ... ... SPL 0,