---
title: "Chess"
id: 51714
type: "computer_media"
slug: "chess-2"
url: "http://localhost/computer_media/chess-2/"
markdown_url: "http://localhost/computer_media/chess-2.md"
published_at: "2023-08-13T23:14:28+00:00"
modified_at: "2026-04-02T16:31:24+00:00"
author: "David Anderson"
featured_image:
  url: "http://localhost/wp-content/uploads/2019/02/20230809-041332.jpg"
excerpt: "A complete chess engine squeezed into a single REM statement."
category:
  - name: "Archived Media"
    slug: "archived-media"
    taxonomy: "category"
    url: "http://localhost/category/archived-media/"
post_tag:
  - name: "Artic Computing"
    slug: "artic-computing"
    taxonomy: "post_tag"
    url: "http://localhost/tag/artic-computing/"
  - name: "Downloadable"
    slug: "downloadable"
    taxonomy: "post_tag"
    url: "http://localhost/tag/downloadable/"
  - name: "TS 1000"
    slug: "ts1000"
    taxonomy: "post_tag"
    url: "http://localhost/tag/ts1000/"
model:
  - name: "Timex/Sinclair 1000"
    slug: "ts-1000"
    taxonomy: "model"
    url: "http://localhost/model/ts-1000/"
genre:
  - name: "Chess"
    slug: "chess"
    taxonomy: "genre"
    url: "http://localhost/type/chess/"
media_type: "Cassette"
download_url: "https://archive.org/download/timex-sinclair-software-archive/Chess (198x)(Artic Computing)(UK)(TS1000)(Cassette).zip"
mediadate: "198x"
producer_company:
  - id: 10657
    title: "Artic Computing"
    type: "company"
    url: "http://localhost/company/artic-computing/"
related_products:
  - id: 11547
    title: "1K Chess"
    type: "product"
    url: "http://localhost/product/1k-chess/"
  - id: 12135
    title: "Chess and Chess Clock"
    type: "product"
    url: "http://localhost/product/chess-3/"
media_type_tags: "Chess"
---

# Chess

This chess program stores its entire game engine as Z80 machine code packed into the REM statement at line 1, with only two additional BASIC lines needed: a SLOW command to enable the display driver and a RAND USR X call to transfer execution into the machine code. Chess piece abbreviations Q, R, B, N, P, K are visible within the REM, likely corresponding to piece-type identifiers encoded in the engine’s data tables.

***

## Source Code

```
   1 REM  FASTVAL LN [V]▝###=C RUN LN [X]▛#AT VAL [T]C▞£( IF AT / SCROLLAT  LPRINT #TAN ▘1▒LN ▙RNDF:ALN ▙RND7#CHR$ 0#:"[J]▟( CLEARLEN #F[-]##A##▞▘ NEW# RETURN C=▖ RETURN#C? RETURNBS"#▖IR▚ACS #C▝▞ ##TAN ▘" COPY PRINT  PLOT  POKE £\~~$ NEXT + FOR * DIM  RUN \,,"\~~£QRBNP[J]M#RND# NEW# RETURNPC#:▘▞▒5 SCROLLRND RETURNNC-I TO  RETURNKC(# RETURNQC"▞▖ RETURNRC▌I STOP RETURNB""#▚ PRINT  FASTVAL  RETURNZS2 RETURN[=]K,LN [V]RND RETURN▝K< PRINT LN [$]PI LET  RETURN C\~~AT  LPRINT # RETURN▘C▌ LET / AND AT  LPRINT  LET 7(PEEK TAN # NEW█5 SLOWRND4▝I LET -▀#▚ FAST PRINT  RETURNZS4 RETURN[=]K0LN [V]RND RETURN C0 RETURN▘4)# RETURN▘4£LN [$]PI# RETURN#S< RETURN#K? LET  LPRINT F+4ABS TAN # RETURN▘CODE [$]PI/ LET  LET  LPRINT #/VAL  FASTVAL STR$  FASTVAL #5RNDRNDLN 8▛LN \~~##▜# LET LN \~~# LPRINT LN /#K▘█# LPRINT SGN ## FASTSTR$ LN /#K▘[(] PRINT LN  RUN PILN ▘PIAT K▝▖▖SGN  LPRINT # LPRINT LN  IF PILN /#K▘▌LN  IF PILN  RUN PI#5WRND# FOR 5INKEY$ RND[Y]**▘▌ /"5#RND)#RND▘0 S▘ FOR  GOSUB [K]TAN UR#LEN K5Y## GOSUB [L]F6█RND▞#5Y#7 FASTVAL #LN [Z]RND RETURN 4;LN  RUN PI#LN  RUN RNDLN  RUN PILN ▙PIC\~~E█RND[X]4 PRINT AT  LPRINT RTAN AT  LPRINT (**[B]TAN ▞▌Y▒5[3]#7#( UNPLOT LN [4]RND RETURN▀4 INPUT 6▛RND#LN  RUN RND5[5]#LN [4]RND RETURN▝ FOR K>=LN ▙PICNOT [T]4 SAVE LN  COPYPI OR LN ▘PI OR S▒LN  FOR PILN [-]PI/TAB ##>/ RAND 5#RNDP#WCOS ▐##TAN 5#RNDO#▐##TAN [J]MINKEY$ RND▞#5Y#7 FASTVAL #LN [Z]RND RETURN▀4D#6▛RNDLN  RUN RNDLN ▙PIC1#-#LN  COPYPI OR [B]LN  PAUSE INKEY$ LN ▘PI OR ##>S▀LN [;]INKEY$ RLN  PAUSE INKEY$ / THENAT  LPRINT (COS UINKEY$ RND RETURN C RETURN5#RND#FF#-#>F##ACS #Q█C▝Q LN  RUN PITAN 5R##LEN █#TAN E▛RND,##Q >#TAN  NEW#5 PAUSE RND▞▌[Y]COS 7( CLS#TAN # OR M█RNDLN (PI OR #TAN 
   2 SLOW
   3 RAND USR X
```