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Speech/Sound Cartridge (26-3144A)

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Home / Hardware - Speech/Sound Cartridge (26-3144A)

Speech Sound Cartridge 26-3144A

The Speech/Sound Cartridge allows a Color Computer to produce monaural synthesized music, sound effects, and speech. It includes a PIC 7040 microcontroller that feeds data from the CoCo into an AY3-8913 Programmable Sound Generator and an SPO256-AL2 Speech Processor. It can produce speech from text, and music in 3 voices.

The sound is played on the Color Computer's monitor or TV through the SND pin on the CoCo's expansion port. The S/SC has a 2K RAM for storing sound effects or speech. There is no ROM-based program in the S/SC (except the ROM for the onboard microcontroller), but the 54 page manual contains complete programming information and many example Color BASIC programs demonstrating the capabilities of the interface.

The S/SC internally doubles the E clock provided on the CoCo's expansion port, and has problems when operated at the CoCo 3's high speed without modification.

Third Party Software

SoundMaster 2.0 by Jim McDowell is an OS-9 Level II program for the CoCo 3 with 512K of RAM. It is a BASIC09 program that provides a graphical interface for designing sounds to be played on the S/SC. It includes device drivers and descriptors for accessing the S/SC at both slow (unmodified) and fast (modified) speeds.


The following games are known to produce sound effects and/or speech with the S/SC if present. Offsite links are to L. Curtis Boyle's list of Tandy (TRS-80) Color Computer Games:


Speech & Sound Pack Modification for High Speed