A/D Flash Type 8-bit MCU with EEPROM
HT66F24D/HT66F25D
Flash Program Memory
The Program Memory is the location where the user code or program is stored. For this device
series 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 of 2Kx16 bits to 4Kx16 bits. 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.
Device
HT66F24D
HT66F25D
Capacity
2K x 16
4K x 16
0000H
0004H
0020H
0024H
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07FFH
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Program Memory Structure
Special Vectors
Within the Program Memory, certain locations are reserved for the reset and interrupts. The location
000H 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.
Rev. 1.10
21
March 25, 2013