MC68HC908KX8 Datasheet, PDF (298/310 Pages) Motorola, Inc – Microcontrollers

MC68HC08KX8 Overview
B.2 Introduction
This appendix describes the differences between the read-only memory
(ROM) version (MC68HC08KX8) and the FLASH version
(MC68HC908KX8) of the microcontroller.
Basically, the differences are:
• FLASH x ROM module changes
– FLASH for ROM substitution
– Partial use of FLASH-related module
• Configuration register programming
• Wider range of operating voltage
B.3 FLASH x ROM Module Changes
This section describes changes between the FLASH and ROM modules.
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FLASH memory and FLASH supporting modules are replaced by ROM
memory, see Figure B-1. In Figure B-1, the user FLASH and user
FLASH vector space are respectively substituted by user ROM and user
ROM vector space.
Additionally, these modules and registers have been eliminated in the
ROM version:
• FLASH burn-in ROM module — Auxiliary FLASH routine codes
• FLASH charge pump module — High-voltage for FLASH
programming
• MENRST module — Helps erased FLASH parts programming,
see 6.4.1.5 Forced Monitor Mode Entry Reset (MENRST)
• SIM reset status register, bit 2 — Refers to MENRST. See 6.8.1
SIM Reset Status Register. MENRST has no function in the
ROM version and reading this bit will return 0.
• FLASH test control register, FLTCR
• FLASH control register, FLCR
• FLASH block protect register, FLBPR
Technical Data
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MC68HC908KX8 • MC68HC908KX2 • MC68HC08KX8 — Rev. 1.0
MC68HC08KX8 Overview
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