MC68HC08AS20 Datasheet, PDF (53/386 Pages) Freescale Semiconductor, Inc – M68HC08 Microcontrollers

Advance Information — MC68HC08AS20
Section 4. Read-Only Memory (ROM)
4.1 Contents
4.2 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
4.3 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
4.2 Introduction
This section describes the 20,480 bytes of user read-only memory
(ROM), 224 bytes of monitor ROM, and 36 bytes of user vectors.
4.3 Functional Description
The user ROM consists of 20,480 bytes of ROM from addresses
$AE00–$FDFF. The monitor ROM and vectors are located from
$FE20–$FEFF. See Figure 2-1. Memory Map.
Thirty-six of the user vectors, $FFDC–$FFFF, are dedicated to
user-defined reset and interrupt vectors.
Security has been incorporated into the MC68HC08AS20 to prevent
external viewing of the ROM contents. This feature ensures that
customer-developed software remains proprietary.
MC68HC08AS20 — Rev. 4.1
Freescale Semiconductor
Advance Information
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