Upgrading from an 8-bit to a 32-bit microcontroller (MCU) typically requires substantial software changes, even when a high-level language like C is employed, because the peripheral architectures are usually different. Not so with NEC Electronics' KX1 microcontroller line. Its members all use the same built-in peripherals--including interface registers--and peripheral architecture. The KX1 32-bit products simply provide more computing power.
With such a unified product line, users can choose a particular MCU based upon the initial needs of an application and then easily replace it with a higher-performance chip from the same line as more features are added. The KX1 32-bit products are based on NEC's V850x processor. NEC's K0 MCU line has the same 8-bit processor architecture. Most of the differences in these two architectures can be hidden by using a C compiler.
The peripheral complement includes the usual timers and serial I/O as well as UART/SPI/I2C support. LIN bus support is also standard. Digital-to-analog converter (DAC) and analog-to-digital converter (ADC) peripherals round out the analog side.
The chips can supply power on reset to other devices. Also, each has its own low-voltage indicator. The FailSafe clock monitors the external clock. It can additionally switch to the internal oscillator if an external clock is not detected, allowing the processor to run under almost any condition.
NEC offers software development tools, including C compilers and debuggers. Header files are provided for the KX1 peripherals. The 8-bit µPD780101 costs $2.00 and the 32-bit µPD703217 is priced at $5.00, both in 10,000-unit quantities.
NEC Electronics Inc., www.necel.com; (408) 588-6000.