Checkers – August 1980

By sheer coincidence, Activision and Atari both published VCS versions of the board game checkers roughly a month apart. Activision’s Checkers, by Alan Miller, started reaching stores in August, beating Atari’s effort to retailers. While it looks graphically more interesting, whether or not it bests the version published by his former employer depends on what you value in your board game translations.

Checkers, like chess, backgammon and bulls & cows, is an ancient game with origins dating back to Mesopotamia and Egypt, and numerous variations of the game exist today throughout the globe. The modern ruleset seen in both of these VCS renditions dates back to 1500s France and is generally known as either draughts or checkers in British or American English, respectively. Under this ruleset, pieces can only move forward diagonally, and if it’s possible for a piece to jump an opposing player’s, they must do so even if it puts them in a bad position. If it’s possible to jump a piece and then immediately take another piece, then that must also be done. This is key to the strategy of checkers under these rules – forcing your opponent to take your pieces and put themselves in a position to get jumped – possibly more than one time. Once a piece reaches the far side of the board they are “kinged” and can move both forwards and backwards on diagonals. The game ends when one side runs out of pieces or if there’s a draw.

This is certainly the ruleset seen most commonly in the history of computing; checkers was among the earliest computer games ever written, with British computer scientist (and games lover) Christopher Strachey producing a working, complete draughts program on the Ferranti Mark 1 computer at the University of Manchester in July 1952. Strachey had an initial-but-nonfunctional version in May 1951, but continued working on it over the next year thanks to encouragement from famed computer scientist Alan Turing, though Turing felt his time could have been better spent on other, less frivolous programming efforts. His version weighed the value of each move in a program tree, selecting whichever would be the most advantageous after a non-exhaustive consideration of its next move. Unusually for the time, his draughts program used a cathode-ray tube display – the 3 and 5 storage tube displays were used to show the current game board and a move preview, respectively, with moves input using a series of switches and the computer’s moves listed on a teletype.

Strachey gave a talk about the program in Toronto later in 1952, which in turn may have inspired American AI specialist Arthur Samuel to work on his own checkers program at IBM. Samuel had a computer background already through his work with the ILLIAC computer at the University of Illinois, and as a way to get some attention (and potentially funding) for the program, he started designing a checkers program capable of beating a human opponent, though he left it unfinished when he took a job at IBM in 1949. The company was debuting its new IBM 701 computer around 1952, coincidentally when Strachey was on the continent giving his talk, and Samuel decided to return to checkers as a test program for its instruction set. An initial version was completed that year, but Samuel continued to refine it over the course of the decade, gaining notoriety when it was demonstrated on national TV in February 1956. Samuel’s game pioneered the idea of alpha-beta pruning: effectively pruning off any possibilities that were moving in a less advantageous direction before the computer wasted time following the branch further. Furthermore, in 1955 he designed his checkers program to “learn” from bad moves, as it saved the results of moves in completed games and could adjust the weight in its move tree based on how effective they were, to a certain limit of storage space.

Both Strachey and Samuel’s games were written as early experiments into artificial intelligence, with the player going up against a computer opponent, and checkers, like chess, would serve as a barometer for how powerful a computer –and the programming behind it – could be. A version of the board game for DEC’s PDP computers was written by Paul Klinkman in 1971, and a BASIC rendition originally by an Alan Segal appeared in the pages of David Ahl’s 101 BASIC Computer Games in 1973.

John Collins’ Checkers program, written in Bally BASIC.

On home consoles, checkers as a game had a rough start. Checkers games were advertised in 1978 and 1979 for the Fairchild Channel F and Bally Professional Arcade, but neither of these renditions would see the light of day for some time. The earliest console take on the game would be a Checkers program initially written by John Collins for the Bally Arcade in BASIC back in May 1979 and sold on cassette tape the following month, with refinements by other developers over the next couple years. This didn’t use the controller, but rather had players typing in their moves using the console’s keypad using X and Y coordinates. It’s awkward, and will crash completely if you type in coordinates outside of its range, but the game itself plays pretty well, with the computer having a predetermined amount of time to consider its moves. Bally’s own Checkers game would go unreleased until 1985, when enthusiast Mike White got a hold of a prototype cartridge and sold copies of it through the Arcadian newsletter. While this is playable, the computer puts up such a poor fight that it’s entirely likely that the game AI was never fully completed and refined before its cancellation.

The Channel F Checkers cartridge didn’t see the light of day until Zircon purchased the system rights and started clearing out Fairchild’s unsold stock.

Fairchild’s Checkers game was completed and even promoted prior to the company liquidating its video game division to Zircon, and in August 1980 the company issued a press release announcing that it, alongside three other unreleased Channel F games, would now be available for purchase through its product catalog. The Channel F checkers program is a worthy opponent to this pretty inexperienced player, but arguably the most notable legacy this game has as the rarest and most expensive commercial Channel F release, as unlike the other late-release titles it appears Checkers was not a strong enough seller to justify Zircon doing any other production runs beyond this initial one, and it’s likely that this was just leftover Fairchild stock.

The Channel F and the VCS weren’t the only platforms hosting the digital board game in 1980, though, as Mattel released Checkers alongside the Intellivision platform around February as the company continued its slow rollout across North America for the game system. Due to the delays with the Channel F cart and the niche situation of John Collins’ Bally BASIC take, this Intellivision version was functionally the first home console checkers game to get a wide release. This game features two computer skill levels and a feature that allows players to ask the computer to recommend your next move, though this tends to be more beneficial for your opponent, in my experience. According to an interview with Scott Stilphen, APh developer David Rolfe said the original release of this game had a bug in its look-ahead algorithm that would cause it to go one step too far and overflow the RAM boundaries. The bugfixed version of the game has slightly different sound effects, though Rolfe did not remember making that change. Checkers was not a huge seller for Mattel, moving 40,000 units in 1980 and ending up at 120,500 shipped copies by mid-1983. The game would be included in INTV’s Triple Challenge cart alongside Chess and Backgammon in 1987 which, much like Zircon’s Checkers game, is something of a coveted and rare collectable today.

The Intellivision rendition of checkers.

Which brings us to the first of the two VCS checkers releases. This was Miller’s debut game upon exiting Atari and founding Activision in October, 1979, an ordeal that required him to put a second mortgage on his condo for startup funding after only receiving $500,000 from investors at Sutter Hill Ventures. According to an interview with Al Backiel, Miller’s Activision cartridge originally started off as a 3D version that would use red/blue glasses to produce its effect. This didn’t work out for two reasons: for one, the limitations of the VCS’s horizontal display meant there wasn’t much room to get the appropriate offset for the stereoscopic display; and two, given that color TVs weren’t precisely machine-calibrated until microprocessors like RCA’s 1802 came along in the mid-1970s to do that work, there were a lot of color sets in homes at the time weren’t reproducing the colors accurately enough for the glasses to work. Miller would drop the 3D and simply focus on finishing the rest of the game.

Even without the 3D glasses, however, Miller retained the visual language he’d intended, with all of the chips appearing as though they’re being seen at an angle. Combined with no real flicker outside of your cursor, this winds up making Checkers look pretty appealing in a way that the other board game translations on the hardware don’t. On a technical note, unlike the other VCS games like Video Chess and Backgammon that cut the display while the computer considers its moves and just show flashing colors, Miller’s Checkers maintains vertical blanking while the computer is thinking, simply blacking out the display. This makes it play nicely with modern upscalers and television displays that otherwise struggle to maintain a signal lock.

Several “kinged” pieces on the board late into a game.

Alan Miller’s game is certainly a leaner package than Carol Shaw’s incoming Atari-released version, in large part because it’s a 2-kilobyte game compared to her 4-kilobyte cartridge. His cartridge gives you three difficulty levels to work with, as well as a two-player mode, in case you don’t have a board handy. The right difficulty switch allows the player to swap the red and white pieces, with the first player always playing whichever side is on the bottom of the screen. Much like in the previous strategy games we’ve seen on the VCS – Video Chess, Backgammon and 3D Tic-Tac-Toe – Miller’s computer will consider its moves by playing forward possibilities for a predetermined length of time, going between 5 and 15 seconds in the lowest difficulty to between 2 and 4 minutes at the highest. According to an interview with Shaw, both she and Miller had consulted with Arthur Samuel for their respective computerized checkers programs, only learning about each other’s involvement after the fact; this may be a factor in why Miller took this particular approach, or perhaps he consulted Bob Whitehead, the co-author of Video Chess, on how they handled moves there. In the manual, Miller notes that while the computer opponent can be tough, it still had a fundamental weakness at endgame and frequently will not move in for the kill even when it has an advantage.

The pieces on Miller’s game are especially well-defined compared to other versions.

Like the other board game translations there aren’t a lot of reviews out there for Checkers, but Video covered all four of Activision’s initial games, including this one. Bill Kunkel and Arnie Katz noted in their column that the computer opponent could provide a good tussle for players, even if it was weak in the endgame. Beyond that there is little to go on as far as Checkers‘ public perception. Given that it is one of the more difficult Activision games to find today, however, it probably wasn’t terribly popular.

Alan Miller, meanwhile, was just getting started at Activision, and has quite a few more hits up his sleeves, though his next published work wouldn’t arrive until 1981’s Tennis. In his interview with Backiel, Miller remarked that he had also worked on a rendition of Othello, aka reversi, for the VCS at Activision that ultimately went unreleased. Given that Atari published its own Othello cartridge in early 1981, it begs the question on whether or not Miller opted to halt work on the game upon learning Atari was about to repeat the same release pattern that Checkers went through, or perhaps because his cartridge just wasn’t selling that well. In either case, Checkers is a solid outing in a period of interesting strategy game releases, and is another showcase for the sort of programs Activision would be putting out in the years ahead: visually striking and mechanically solid.

Sources:

Alan Miller, interview with Al Backiel, Al Backiel, Digital Press, 2003

A New Era Begins: Activision Exploits Atari’s Success, Bill Kunkel and Arnie Katz, Video, December 1980

Activision’s Alan Miller: Games in Perspective, Bill Kunkel, Electronic Games, July 1982

Arcadian, May 4, 1979, Dec. 20 1985

Checkers, blueskyrangers.com

David Rolfe, interview with Scott Stilphen, ataricompendium.com, 2004

Carol Shaw: Atari’s First Female Video Game Developer, Benj Edwards, Vintage Computing and Games, Oct. 12, 2011

Programming Enter: Christopher Strachey’s Draughts Program, David Link, Computer Resurrection, Winter 2012/2013

Special Fairchild Video Game News from Zircon press release, Aug. 26 1980

The Games that Helped AI Evolve, IBM.com

Some Studies in Machine Learning Using the Game of Checkers, Arthur Samuel, IBM Journal, July 1959