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74
Revision 1.1
G
SuperI/O Module
(Continued)
4.4.2
As described in Section 4.3.2 "Banked Logical Device Reg-
isters" on page 68, each functional block is associated with
a Logical Device Number (LDN). This section provides the
register descriptions for each LDN.
Logical Device Control and Configuration
The register descriptions in this subsection use the follow-
ing abbreviations for Type:
R/W
R
= Read/Write
= Read from a specific address returns the
value of a specific register. Write to the
same address is to a different register.
= Write
= Read Only
R/W1C = Read/Write 1 to Clear. Writing 1 to a bit
clears it to 0. Writing 0 has no effect.
W
RO
4.4.2.1
Table 4-6 lists the registers which are relevant to configura-
tion of the Real-Time Clock (RTC). Only the last registers
(F0h-F3h) are described here (Table 4-7). See Table 4-3
"Standard Configuration Registers" on page 71 for descrip-
tions of the other registers.
LDN 00h - Real-Time Clock
Table 4-6. Relevant RTC Configuration Registers
Index
Type
Configuration Register or Action
Reset
Value
30h
R/W
Activate.
When bit 0 is cleared, the registers of this logical device are not accessible.
1
00h
60h
R/W
Standard Base Address MSB register.
Bits [7:3] (for A[15:11]) are RO, 00000b.
00h
61h
R/W
Standard Base Address LSB register.
Bit 0 (for A0) is RO, 0b.
70h
62h
R/W
Extended Base Address MSB register.
Bits [7:3] (for A[15:11]) are RO, 00000b.
00h
63h
R/W
Extended Base Address LSB register.
Bit 0 (for A0) is RO, 0b.
72h
70h
R/W
Interrupt Number.
08h
71h
R/W
Interrupt Type.
Bit 1 is R/W; other bits are RO.
00h
74h
RO
Report no DMA assignment.
04h
75h
RO
Report no DMA assignment.
04h
F0h
R/W
RAM Lock register (RLR).
00h
F1h
R/W
Date of Month Alarm Offset register (DOMAO).
Sets index of Date of Month Alarm
register in the standard base address.
00h
F2h
R/W
Month Alarm Offset register (MONAO).
Sets index of Month Alarm register in the
standard base address.
00h
F3h
R/W
Century Offset register (CENO).
Sets index of Century register in the standard base
address.
00h
1.
The logical device registers are maintained, and all RTC mechanisms are functional.