Samsung S3F80JB - Manual (Page 239)

S3F80JB I/O PORTS
9-1
9
I/O PORTS
OVERVIEW
The S3F80JB microcontroller has two kinds of package and different I/O number relating to the package type:
44-QFP package has five bit-programmable I/O ports, P0–P3 and P4. Four ports, P0–P2 and P4, are 8-bit ports
and P3 is a 6-bit port. This gives a total of 38 I/O pins.
32-SOP package has four bit-programmable I/O ports, P0–P3. Three ports, P0–P2, are 8-bit ports and P3 is a 2-
bit port. This gives a total of 26 I/O pins.
Each port is bit-programmable and can be flexibly configured to meet application design requirements. The CPU
accesses ports by directly writing or reading port registers. No special I/O instructions are required.
For IR applications, port0, port1, and port2 are usually configured to the keyboard matrix and port 3 is used to IR
drive pins.
Table 9-1, 9-2 and 9-3 give you a general overview of S3F80JB I/O port functions.