variant contains only Mattel-specific game phrases, including the energetic phrase "Mattel Electronics Presents," phrases for digits, and a couple additional game phrases. It does not contain the allophones found in the SP0256-AL2 or SP0256-019. Mattel only released five games with support for this device. SP0256-017 The SP0256-017 comes from a talking clock, and contains phrases specific to the talking clock. The SP0256-017 was sold by Radio Shack under the Archer brand as part number 276-1783. The part set also contained the SPR016-117, an external serial speech ROM. The vocabulary included the numbers (in combination) through 59, appropriate for a spoken clock. The onboard memory also provided for synthesizing the following phrases: A.M., P.M., It is, Hour, Minute, Hundred Hour, Good Morning, Attention Please, Please Hurry, and three Melodies named A, B and C. SP0256-019 The Magnavox Odyssey²'s The voice attachment uses the SP0256-019. This variant included the same allophones as the SP0256-AL2 (but an external ROM IC is required for the allophones), along with some Odyssey²-specific game phrases. SP0264-021 Used in a prototype Fuzzbuster radar detector, the SP0264-021 has relevant phrases and is pin compatible to the SP0256 series. FPGA emulation An FPGA implementation of a classic eighties speech synthesizer SPO256, done for the Retro Challenge October 2017 by Niels Moseley, is available on his GitHub account. References External links SPO256B Datasheet SPO256 Applications Manual SPR-16 Speech ROM Data Sheet SPR-32 Speech ROM Data Sheet SPR-128 Speech ROM Data Sheet US. Patent 4,296,279 Mask ROM Contents Summaries for various SPO256 Variants FPGA Verilog implementation of the SPO256 by Niels Moseley Sound chips Speech synthesis