B.G. Micro Computalker Speech Board

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Text to speech for the PC era

B.G. Micro sold this board as a PC/XT-compatible text-to-speech system. Its two central General Instrument chips divide the work: CTS256A-AL2 translates English text into allophone commands, and SP0256-AL2 synthesizes the resulting voice. The familiar electronic delivery comes from building speech out of sound elements rather than selecting a fixed list of complete words.

An ISA card with a serial input

The card’s edge connector supplies power from an 8-bit ISA slot. Speech data arrives through the DB-25 RS-232 connector rather than through ISA bus registers. This makes the card unusual among PC expansion boards: the computer talks to it through a serial port. Its built-in speaker provides audio, with an additional RCA audio connection on the bracket.

Period B.G. Micro advertising also described standalone use with an external power supply and a computer equipped with RS-232. It advertised a 1,500-byte text buffer and a handshake line, allowing the sender to pace the text as speech was generated.

The board pictured here

This specimen carries a ©1986 B.G. Micro board marking and an 8703 stamp. The SP0256-AL2 and CTS256A-AL2 markings are readable, alongside RAM, supporting logic, crystals, a six-position switch bank, and the speaker. The copyright marking identifies the board design’s date; it does not, by itself, establish an exact production date.

Documentation and software

The preserved documentation collection includes board photographs, scanned instructions, chip documentation, and software files. It records the Computalker name alongside Speech Synthesizer Card and Voice Synthesizer Card. Consult the instructions for switch settings, cabling, and power connections before operating a surviving board.

Specifications

Speech synthesizer

SP0256-AL2

Text converter

CTS256A-AL2

Text input

RS-232, DB-25 connector

Power connection

8-bit ISA slot; standalone operation also advertised

Audio

Onboard speaker and RCA connection

Advertised text buffer

1,500 bytes

Documentation and downloads

• B.G. Micro documentation and software archive

  Scanned documents, chip information, photographs, and software files.