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108
Revision 3.0
G
SuperI/O Module
(Continued)
Table 4-7.
RTC Configuration Registers
Bit
Description
Index F0h
When any non-reserved bit in this register is set to 1, it can be cleared only by hardware reset.
RAM Lock Register - RLR (R/W)
7
Block Standard RAM.
0: No effect on Standard RAM access. (Default)
1: Read and write to locations 38h-3Fh of the Standard RAM are blocked, writes ignored, and reads return FFh.
Block RAM Write.
0: No effect on RAM access. (Default)
1: Writes to RAM (Standard and Extended) are ignored.
Block Extended RAM Write.
This bit controls writes to bytes 00h-1Fh of the Extended RAM.
0: No effect on the Extended RAM access. (Default)
1: Writes to bytes 00h-1Fh of the Extended RAM are ignored.
Block Extended RAM Read.
This bit controls read from bytes 00h-1Fh of the Extended RAM.
0: No effect on Extended RAM access. (Default)
1: Reads to bytes 00h-1Fh of the Extended RAM are ignored.
Block Extended RAM.
This bit controls access to the Extended RAM 128 bytes.
0: No effect on Extended RAM access. (Default)
1: Read and write to the Extended RAM are blocked: writes are ignored and reads return FFh.
Reserved.
6
5
4
3
2:0
Index F1h
Date Of Month Alarm Register Offset Register - DOMAO (R/W)
7
Reserved.
Date of Month Alarm Register Offset Value.
6:0
Index F2h
Month Alarm Register Offset Register - MANAO (R/W)
7
Reserved.
Month Alarm Register Offset Value.
6:0
Index F3h
Century Register Offset Register - CENO (R/W)
7
Reserved.
Century Register Offset Value.
6:0