μCOM-4 The
μCOM-4 (μPD751) is NEC's original single-chip 4-bit microprocessor, announced in 1973. •
μPD752 - 8-bit I/O port •
μPD757 - Keyboard and display controller •
μPD758 - Printer controller
μCOM-41 The
μCOM-41 (μPD541) is a
PMOS microprocessor in a 42-pin package. The following peripheral integrated circuits were available: •
μPD542 - ROM plus RAM •
μPD543 - ROM plus I/O port
μCOM-42 The
μCOM-42 (μPD548) is a 4-bit
PMOS microcontroller in a 42-pin package. It has built-in ROM (1920 × 10 bit) and RAM (96 × 4 bit) as well as keyboard, display, and printer controllers. The μPD548 requires a power supply of -10V and the outputs can switch up to -35V. A ROM-less chip (μPD555) in a 64-pin quad-in-line package was available for hardware and software development.
μCOM-43 through μCOM-46 The
μCOM-43 series consists of more than 10 different 4-bit microcontrollers. Broadly speaking, there are
PMOS devices (μPD500 series),
NMOS devices (μPD1500 series,
μCOM-43N ), and
CMOS devices (μPD650 series,
μCOM-43C ). The
μCOM-43,
μCOM-44,
μCOM-45, and
μCOM-46 have the same basic instruction set. They differ in the amount of ROM and RAM, the number of I/O pins, and the package (28-pin or 42-pin). A ROM-less chip (μPD556) in a 64-pin quad-in-line package was available for hardware and software development. Beginning in 1980, they there were gradually replaced by the μCOM-75 series (see below).
μCOM-47 The
μCOM-47 (μPD766) is a 4-bit
NMOS microcontroller in a 64-pin package. It has built-in ROM and RAM as well as keyboard, display, and printer controllers.
μCOM-75 The
μCOM-75 series consists of 4-bit microcontrollers. Only the first device in the series, the μPD7520, was still developed in PMOS technology. All subsequent microcontrollers in the series (μPD7502 etc.) used CMOS. A ROM-less chip (μPD7500) in a 64-pin quad-in-line package was available for hardware and software development. By 1982 the μCOM-75 series was referred to as the μPD7500 series and later replaced by the 75X and 75XL series. == μCOM-8 series ==