Like the Intellivision chip-set, the Intellivoice chip-set was developed by General Instrument. The SP0256-012 orator chip has 2KB ROM inside, and is used to store the speech for numerical digits, some common words, and the phrase "Mattel Electronics presents". Speech can also be processed from the Intellivoice's SP650 buffer chip, stored and loaded from cartridge memory. That buffer chip has its own I/O and the Intellivoice has a 30-pin expansion port under a removable top plate. Mattel Electronics planned to use that connector for wireless hand controllers.