W83977A Winbond Electronics Corp America, W83977A Datasheet - Page 79

• Manufacturer Part Number: W83977A
• Description: Winbond I/O
• Manufacturer: Winbond Electronics Corp America

W83977TF
PRELIMINARY
7. GENERAL PURPOSE I/O
W83977TF provides 23 Input/Output ports that can be individually configured to perform a simple
basic I/O function or a pre-defined alternate function. Those 23 GP I/O ports are divided into three
groups, the first group contains 8 ports, the second group contains only 7 ports, and the third group
contains 8 ports. Each port in first group corresponds to a configuration register in logical device 7,
the second group in logical device 8, and the third group in logical device 9. Users can select those
I/O ports functions by independently programming those configuration registers. Figure 7.1, 7.2, and
7.3 respectively show the GP I/O port's structure of logical device 7, 8, and 9. Right after Power-on
reset, those ports default to perform basic I/O functions.
Figure 7.1
Publication Release Date:March 1998
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Revision 0.62