MC68HC908KX8 Datasheet, PDF (300/310 Pages) Motorola, Inc – Microcontrollers

MC68HC08KX8 Overview
B.3.2 Partial Use of FLASH-Related Module
Section 18. Monitor ROM (MON) was written having FLASH as user
memory and user vector space.
MON functions are maintained for the ROM version. MON will allow
execution of code in random-access memory (RAM) or ROM and
provide ROM memory security⁽¹⁾. The memory programming interface,
though, will have no effect in ROM version.
An assumption that must be made for the ROM version is that the reset
vector will always have a value different from $0000, corresponding to
the user code start address. For this reason, force entry into monitor
mode, described in 18.5 Monitor Mode Entry and in 18.5.2 Forced
Monitor Mode, is not applicable to the ROM version. The MENRST
module has been eliminated from the ROM version.
The security function described in 18.11 Security also applies to the
user ROM memory for the ROM version.
B.4 Configuration Register Programming
Functionally, the terms MOR (mask option register) and CONFIG
(configuration register) can be used interchangeably. MOR and CONFIG
are equivalent since both define the same module functionality options
through the registers bits. As a naming convention, though, configuration
registers are named MOR for a ROM version and CONFIG for a FLASH
version.
Some modules affected by the configuration register bits make
reference to default values of these bits and have recommendation
notes on programming them.
Technical Data
300
1. No security feature is absolutely secure. However, Motorola’s strategy is to make reading or
copying the ROM difficult for unauthorized users.
MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 — Rev. 1.0
MC68HC08KX8 Overview
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