The SPRS075D datasheet, published in October 1998, introduces the detailed information of the 565A chip, including its advanced multibus architecture, 40-bit arithmetic logic unit, 17- × 17-bit parallel multiplier, compare, select, and store unit, exponent encoder, two address generators, data bus, extended addressing mode, 64K x 16-bit on-chip RAM, 16K x 16-bit on-chip ROM, enhanced external parallel interface, etc.