W83977AF Information Storage Devices, Inc, W83977AF Datasheet - Page 15

• Manufacturer Part Number: W83977AF
• Description: W83877TF Plus Kbc, Cir, RTC
• Manufacturer: Information Storage Devices, Inc

Real Time Clock
General Purpose I/O Ports
Package
14 programmable general purpose I/O ports; 6 dedicate, 8 optional
General purpose I/O ports can serve as simple I/O ports, interrupt steering inputs, watching dog
128-pin PQFP
27 bytes of clock, On-Now, and control/status register (14 bytes in Bank 0 and 13 bytes in Bank
2); 242 bytes of general purpose RAM
BCD or Binary representation of time, calendar, and alarm registers
Counts seconds, minutes, hours, days of week, days of month, month, year, and century
12-hour/ 24-hour clock with AM/PM in 12-hour mode
Daylight saving time option; automatic leap-year adjustment
Dedicated alarm (Alarm B) for On-Now function
Programmable delay-time between panel switch off and power supply control
Software control power-off; various and maskable events to activate system Power-On
System Management Interrupt ( SMI ) for panel switch power-off event
timer output, power LED output, infrared I/O pins, general purpose address decoder, KBC control
I/O pins.
W83977F/ W83977AF
Publication Release Date: March 1998
-4-
PRELIMINARY
Revision 0.58