Its firmware was proprietary, and its chief communications with the Z80 were indications of what word it had recognized, and what probability of confidence it calculated for the match.
Late in its development, Halcyon had to be re-designed to use Laserdisc players because CED units were put out of production by RCA.
[clarification needed][citation needed] Speech synthesis was produced using a licensed text-to-speech algorithm included as part of the base Halcyon Operating System, including a special English vocabulary which would correctly pronounce hundreds of proper names.
Speech samples would be compared against allowed responses, and a match, along with probability of accuracy, would be sent to the Halcyon main processor.
Probability ranking could trigger Halcyon to ask the player to repeat their choice when it received a poor match to all expected responses.
Mis-recognitions were chiefly the result of a sample of speech given sufficient probability to match one of the anticipated words or phrases.
Halcyon was intended to have a voice much like the Hal 9000, but memory constraints prohibited the use of tailored speech parameters for the Votrax synthesizer that was built into the console.
Modified spellings were also used where needed to correct pronunciation issues, though this did not apply to words such as user names typed by the player.
A scene with an item used or removed would have separate animation and graphics, allowing for 2 additional audio tracks, again without lip sync.
Halcyon's game authoring method would easily accommodate playing Dragon's Lair, except for the restraint that speech recognition would take too long to process each move before the time allowed would expire, limiting it to keyboard-only use.
), applicable timers (real-time events would suspend when games were saved), and their trained speech sampled data.