AMD SC1200, SC1201 Logical Device Control and Configuration, Relevant RTC Configuration Registers

32579B SuperI/O Module

5.4.2Logical Device Control and Configuration

As described in Section 5.3.2 "Banked Logical Device Reg- isters" on page 92, each functional block is associated with a Logical Device Number (LDN). This section provides the register descriptions for each LDN.

The register descriptions in this subsection use the follow- ing abbreviations for Type:

• R/W = Read/Write

•R = Read from a specific address returns the value of a specific register. Write to the same address is to a different register.

•	W	=	Write
•	RO	=	Read Only
•	R/W1C	= Read/Write 1 to Clear. Writing 1 to a bit
			clears it to 0. Writing 0 has no effect.

5.4.2.1LDN 00h - Real-Time Clock

Table 5-6lists the registers which are relevant to configura- tion of the Real-Time Clock (RTC). Only the last registers (F0h-F3h) are described here (Table 5-7). See Table 5-3 "Standard Configuration Registers" on page 95 for descrip- tions of the other registers.

Table 5-6. Relevant RTC Configuration Registers

			Reset
Index	Type	Configuration Register or Action	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	00h
		register in the standard base address.
F2h	R/W	Month Alarm Offset register (MONAO). Sets index of Month Alarm register in the	00h
		standard base address.
F3h	R/W	Century Offset register (CENO). Sets index of Century register in the standard base	00h
		address.

1.The logical device registers are maintained, and all RTC mechanisms are functional.

98 AMD Geode™ SC1200/SC1201 Processor Data Book