This Z8® subfamily features an Expanded Register File (ERF) to allow access to register-mapped peripheral and I/O circuits. Four basic address spaces are available to support a wide range of configurations: Program Memory, Register File, Data Memory, and ERF. The Working Register File is composed of 236/237 bytes of general-purpose registers, 4 I/O port registers, and 15 control and status registers. The ERF consists of 12 control registers.
