S3F80P5_UM_ REV1.00 ADDRESS SPACE
2 ADDRESS SPACE
OVERVIEW
The S3F80P5 microcontroller has two types of address space:
— Internal program memory (Flash memory)
— Internal register file
A 16-bit address bus supports program memory operations. A separate 8-bit register bus carries addresses and
data between the CPU and the register file.
The S3F80P5 has a programmable internal 18-Kbytes Flash ROM. An external memory interface is not
implemented.
There are 333 mapped registers in the internal register file. Of these, 272-byte are for general-purpose use. (This
number includes a 16-byte working register common area that is used as a “scratch area” for data operations, a
192-byte prime register area, and a 64-byte area (Set 2) that is also used for stack operations). Twenty-two 8-bit
registers are used for CPU and system control and 39 registers are mapped peripheral control and data registers.
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