FS9912

Rev. 3.6

14/34

11. unction Description

11.1 CPU Core

11.1.1 CPU Core Block Diagram

Program Counter

8-Level Stack

Program Memory

Control Unit

ALU

Status Flag

FSR

Interrupt Unit

General

Data Memory

Data Bus

[7:0]

Address Bus

[7:0]

Oscillator

Clock Generator

Interrupt Event

Input

11.1.2 Program Memory Organization

FS9912 CPU has a 12-bit program counter capable of address an 4k x 16 program memory space.

The reset vector is at 0000h and the interrupt vector is at 0004h.

Program Conter

Stack Level 1

Stack Level 2

Stack Level 3

Stack Level 4

Reset Vector

Interrupt Vector

0000h

0004h

0FFFh

Stack Level 5

Stack Level 6

Stack Level 7

Stack Level 8