The Zilog Z8 is a microcontroller architecture, originally introduced in 1979, which today also includes the eZ8 Encore!, eZ8 Encore! XP, and eZ8 Encore! MC families.
Signifying features of the architecture are up to 4,096 fast on-chip registers which may be used as accumulators, pointers, or as ordinary RAM. A 16-bit address space for between 1k and 64k of either OTP ROM or Flash memory are used to store code and constants, and there is also a second 16-bit address space which may be used for large applications.
On chip peripherals include A/D converters, SPI and I²C channels, IrDA encoders/decoders etc. There are versions with from 8 up to 80 pins, housed in PDIP, MLF, SSOP, SOIC and LQFP packages. The eZ8 Encore! series can be programmed and debugged through a single pin serial interface.
The basic architecture, a modified (non-strict) Harvard architecture, is technically very different from the Zilog Z80. Despite this, the instruction set and assembly syntax are quite similar to other Zilog processors: Load/store operations uses the same LD mnemonic (no MOV or MOVEs), typifying instructions such as DJNZ, are the same, and so on.
A free C compiler and IDE can be downloaded from Zilog's website.
Primary competitors include the somewhat similar Microchip PIC family, and all the Intel 8051 descendants. Also more traditional "von Neumann based" single chip microcontrollers may be regarded as competitors, such as the 6800/6809 based Motorola 68HC11, the Hitachi H8 family, and Z80-derivatives, such as Toshiba TLCS-870, to name just a few.
Read more about Zilog Z8: Product Line