MC68HC908MR16/MC68HC908MR32 — Rev. 4.0 Advance Information
MOTOROLA Memory Map 39

Advance Information — MC68HC908MR16/MC68HC908MR32

Section 2. Memory Map

2.1 Contents

2.2 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
2.3 Unimplemented Memory Locations . . . . . . . . . . . . . . . . . . . . .39
2.4 Reserved Memory Locations . . . . . . . . . . . . . . . . . . . . . . . . . .40
2.5 I/O Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
2.6 Monitor ROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53

2.2 Introduction

The central processor unit (CPU08) can address 64 Kbytes of memory
space. The memory map, shown in Figure 2-1, includes:
32 Kbytes of FLASH
768 bytes of random-access memory (RAM)
46 bytes of user-defined vectors
240 bytes of monitor read-only memory (ROM)

2.3 Unimplemented Memory Locations

Some addresses are unimplemented. Ac cessing an unimplemented
address can cause an illegal address reset. In the memory map and in
the input/output (I/O) register summary, unimplemented addresses are
shaded.
Some I/O bits are read only; the write fun ction is unimplem ented. Writing
to a read-only I/O bit has no effect on microcontroller unit (MCU)
operation. In register figures, the write function of read-only bits is
shaded.