MC68HC705JJ7 Datasheet, PDF (21/164 Pages) Freescale Semiconductor, Inc – Microcontrollers

Chapter 2
Memory
2.1 Introduction
This section describes the organization of the memory on the MC68HC705JJ7/MC68HC705JP7.
2.2 Memory Map
The central processor unit (CPU) can address 8 kilobytes of memory space as shown in Figure 2-1. The
memory map includes:
• The erasable programmable read-only memory (EPROM) portion of memory holds the program
instructions, fixed data, user-defined vectors, and interrupt service routines.
• The random-access memory (RAM) portion of memory holds variable data.
• Input/output (I/O) registers are memory mapped so that the CPU can access their locations in the
same way that it accesses all other memory locations.
$1EFF
Figure 2-1. Memory Map
2.3 Input/Output Registers
Figure 2-2 and Figure 2-3 summarize:
• The first 32 addresses of the memory space, $0000–$001F, containing the I/O registers section
• One I/O register located outside the 32-byte I/O section, which is the computer operating properly
register (COPR) mapped at $1FF0
MC68HC705JJ7 • MC68HC705JP7 Advance Information Data Sheet, Rev. 4.1
Freescale Semiconductor
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