W83C553F Datasheet, PDF (112/159 Pages) Winbond – SYSTEM I/O CONTROLLER WITH PCI ARBITER

W83C553F
Electrical Specifications
RTC CMOS RAM Protect 1 Register
Type:
Write only
Bit Description:
Bits [7:0]:
Any value. Writing any value to this port sets a flip-flop which prevents any subsequent access
to addresses 20h - 2Fh of the Real Time Clock address space. This flip-flop is cleared only on
power-on reset. A read has no effect. This register's initial state after reset is in unprotected
mode. This register only exists in PowerPC mode.
RTC CMOS RAM Protect 2 Register
Type:
Write only
Bit Description:
Bits [7:0]:
Any value. Writing any value to this port sets a flip-flop which prevents any subsequent access
to addresses 30h - 3Fh of the Real Time Clock address space. This flip-flop is cleared only on
power-on reset. A read has no effect. This register's initial state after reset is in unprotected
mode. This register only exists in PowerPC mode.
WINBOND SYSTEMS LABORATORY
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