8XC196MC, MD, MH USER’S MANUAL

Table 4-1. Memory Map

Device and

 

 

Hex Address

Description

Addressing Modes

Range

 

 

 

 

MC, MD

MH

 

 

 

 

 

 

FFFF

FFFF

External device (memory or I/O) connected to the

Indirect or indexed

6000

A000

address/data bus

 

5FFF

9FFF

Program memory (internal nonvolatile or external

Indirect or indexed

2080

2080

memory); see Note 1.

 

207F

207F

Special-purpose memory (internal nonvolatile or

Indirect or indexed

2000

2000

external memory)

 

1FFF

1FFF

Memory-mapped SFRs

Indirect or indexed

1FE0

1FE0

 

 

1FDF

1FDF

Peripheral SFRs

Indirect, indexed, or

1F00

1F00

windowed direct

 

1EFF

1EFF

External device (memory or I/O) connected to the

Indirect or indexed

0200

0300

address/data bus (future SFR expansion; see Note 2)

 

01FF

02FF

Upper register file (general-purpose register RAM)

Indirect, indexed, or

0100

0100

windowed direct

 

00FF

00FF

Lower register file (general-purpose register RAM,

Direct, indirect, or indexed

0000

0000

stack pointer, and CPU SFRs)

 

NOTES:

1.After a reset, the device fetches its first instruction from 2080H.

2.The content or function of these locations may change in future device revisions, in which case a pro- gram that relies on a location in this range might not function properly.

4.1.3Program Memory

Program memory occupies a memory partition beginning at 2080H. (See Table 4-1 for the ending address for each device.) This entire partition is available for storing executable code and data. The EA# signal controls access to program memory. Accesses to this address range are directed to internal memory if EA# is held high and to external memory if EA# is held low. For devices without internal nonvolatile memory, the EA# signal must be tied low. EA# is latched at reset.

NOTE

We recommend that you write FFH (the opcode for the RST instruction) to unused program memory locations. This causes a device reset if a program unintentionally begins to execute in unused memory.

4-2

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Intel 8XC196MH, 8XC196MD, 8XC196MC manual Program Memory, Memory Map, Device, Description Addressing Modes