MC68HC908QY2CDW Datasheet, PDF (25/184 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 2
Memory
2.1 Introduction
The central processor unit (CPU08) can address 64 Kbytes of memory space. The memory map, shown
in Figure 2-1, includes:
• 4096 bytes of user FLASH for MC68HC908QT4 and MC68HC908QY4
• 1536 bytes of user FLASH for MC68HC908QT2, MC68HC908QT1, MC68HC908QY2, and
MC68HC908QY1
• 128 bytes of random access memory (RAM)
• 48 bytes of user-defined vectors, located in FLASH
• 416 bytes of monitor read-only memory (ROM)
• 1536 bytes of FLASH program and erase routines, located in ROM
2.2 Unimplemented Memory Locations
Accessing an unimplemented location can have unpredictable effects on MCU operation. In Figure 2-1
and in register figures in this document, unimplemented locations are shaded.
2.3 Reserved Memory Locations
Accessing a reserved location can have unpredictable effects on MCU operation. In Figure 2-1 and in
register figures in this document, reserved locations are marked with the word Reserved or with the
letter R.
MC68HC908QY/QT Family Data Sheet, Rev. 6
Freescale Semiconductor
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