z86e72 ZiLOG Semiconductor, z86e72 Datasheet - Page 46

• Manufacturer Part Number: z86e72
• Description: Otp Microcontroller
• Manufacturer: ZiLOG Semiconductor

PS008704-0507
Register File
Note:
The register file (bank 0) consists of 4 I/O port registers, 236 general-purpose reg-
isters, and 16 control and status registers (R0–R3, R4–R239, and R240–R255,
respectively), plus two expanded registers groups (Banks D and F). Instructions
can access registers directly or indirectly through an 8-bit address field. This
allows a short, 4-bit register address using the register pointer
4-bit mode, the register file is divided into 16 working register groups, each occu-
pying 16 continuous locations. The register pointer addresses the starting location
of the active working register group.
Default setting after reset = 0000 0000
R253 RP
D7 D6 D5
Working register group E0–EF of Bank 0 are only accessed
through working registers and indirect addressing modes.
Figure 22. Expanded Register File Architecture
D4 D3 D2 D1
Figure 23. Register Pointer
D0
Expanded Register
File Pointer
Working Register
Pointer
OTP Microcontroller
(Figure
24). In the
42