Intel 460GX - Manual (Page 265)

Intel® 460GX Chipset Software Developer’s Manual 14-7
SM Bus Controller Configuration
14.3.1 smbhststs–SMBus Host Status Register (I/O)
I/O Address: Base + (00h)
Default Value: 00h
Attribute: Read/Write
This register provides status information concerning the SMBus controller host interface.
14.3.2 smbslvsts–SMBus Slave Status Register (I/O)
I/O Address: Base + (01h)
Default Value: 00h
Attribute: Read/Write
This register provides status information concerning the SMBus controller slave interface.
Bit Description
7:5 Reserved.
4 Failed (FAILED)–R/WC. 1 = Indicates that the source of SMBus interrupt was a failed bus
transaction, set when KILL bit is set (SMBHSTCNT register). 0 = SMBus interrupt not caused by
KILL bit. This bit is only set by hardware and can only be reset by writing a 1 to this bit position.
3 BUS COLLISION(BUS_ERR)–R/WC. 1 = Indicates that the source of SMBus interrupt was a
transaction collision. 0 = SMBus interrupt not caused by transaction collision. This bit is only set
by hardware and can only be reset by writing a 1 to this bit position.
2 Device Error (DEV_ERR)–R/WC. 1 = Indicates that the source of SMBus interrupt was the
generation of an SMBus transaction error. 0 = SMBus interrupt not caused by transaction error.
This bit is only set by hardware and can only be reset by writing a 1 to this bit position.
Transaction errors are caused by:
Illegal Command Field
Unclaimed Cycle (host initiated)
Host Device Time-out
1 SMBus Interrupt (INTER)–R/WC. 1 = Indicates that the source of SMBus interrupt was the
completion of the last host command. 0 = SMBus interrupt not caused by host command
completion. This bit is only set by hardware and can only be reset by writing a 1 to this bit
position.
0 Host Busy (HOST_BUSY)–RO. 1 = Indicates that the SMBus controller host interface is in the
process of completing a command. 0 = SMBus controller host interface is not processing a
command. None of the other registers should be accessed if this bit is set.
Bit Description
7:5 Reserved.
4 Shadow2 Status (SHDW2_STS)–R/WC. 1 = Indicates that the source of SMBus interrupt or
resume event was a slave cycle address match of the SMBSHDW2 port. 0 = SMBus interrupt
not caused by address match to SMBSHDW2 port. This bit is only set by hardware and can only
be reset by writing a 1 to this bit position.
3 Shadow1 Status (SHDW1_STS)–R/WC. 1 = Indicates that the source of SMBus interrupt or
resume event was a slave cycle address match of the SMBSHDW1 port. 0 = SMBus interrupt
not caused by address match to SMBSHDW1 port. This bit is only set by hardware and can only
be reset by writing a 1 to this bit position.