HT85F2240 datasheet(27/147 Pages) HOLTEK

27 / 147 page

Rev. 1.10

�7 of 147

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A/D Flash 8051 Core Low Pin Count MCU

HT85F2230/HT85F2240

17 Flash Program Memory

The Program Memory is the location where the user code or program is stored. For these devices

the Program Memory is Flash type, which means it can be programmed and re-programmed

a large number of times, allowing the user the convenience of code modification on the same

device. By using the appropriate programming tools, these Flash devices offer users the flexibility

to conveniently debug and develop their applications while also offering a means of field

programming and updating.

Structure

The Program Memory has a capacity from 2K×8 to 4K×8. The Program Memory is addressed by

the Program Counter and also contains data, table information and interrupt entries. Table data,

which can be setup in any location within the Program Memory, is addressed by a separate table

pointer register.

Special Vectors

Within the Program Memory, certain locations are reserved for the reset and interrupts. The

location 0000H is reserved for use by the device reset for program initialisation. After a device

reset is initiated, the program will jump to this location and begin execution.

000H

00�H

08BH

Reset

Interr�pt

Vector

8 bits

HT8�F��0

7FFH

FFFH

Reset

Interr�pt

Vector

8 bits

HT8�F��40

Program Memory Structure

HT85F2240 Datasheet(PDF) 27 Page - Holtek Semiconductor Inc