
Hub Interface-to-PCI Bridge Registers (D30:F0)
7-8
82801AA and 82801AB ICH Datasheet
7.1.16
SECSTS—Secondary Status Register (HUB-PCI—D30:F0)
Offset Address:
Default Value:
1E–1Fh
0280h
Attribute:
Size:
R/W
16 bits
For the writable bits in this register, writing a ‘1’ will clear the bit. Writing a ‘0’ to the bit will have
no effect.
Bit
Description
15
ICH (82801AA):
Detected Parity Error (DPE) —R/WC.
1 = ICH (82801AA) detected a parity error on the PCI bus.
0 = This bit is cleared by software writing a 1.
ICH0 (82801AB):
Detected Parity Error—RO. Hardwired to ‘0’.
14
Received System Error (SSE) —R/WC.
1 =
SERR# assertion is received on PCI.
0 = This bit is cleared by software writing a 1.
13
Received Master Abort (RMA) —R/WC.
1 = hub interface to PCI cycle is master-aborted on PCI.
0 = This bit is cleared by software writing a 1.
12
Received Target Abort (RTA) —R/WC.
1 = hub interface to PCI cycle is target-aborted on PCI. For “completion required” cycles from the
hub interface, this event should also set the Signaled Target Abort in the Primary Status Register in
this device, and the ICH must send the “target abort” status back to the hub interface.
0 = This bit is cleared by software writing a 1.
11
Signaled Target Abort (STA) —RO. The ICH does not generate target aborts and does not forward
the target abort response from the hub interface to the PCI interface.
10:9
DEVSEL# Timing Status—RO.
01h = Medium timing.
8
ICH (82801AA):
Data Parity Error Detected—R/WC
1 = The ICH (82801AA) sets this bit when all of the following three conditions are met:
- The Parity Error Response Enable bit in the Bridge Control Register (bit 0, offset 3Eh) is set
- USB, AC’97 or IDE is a Master
- PERR# asserts during a write cycle
OR
a parity error is detected internally during a read cycle
0 = This bit is cleared by software writing a 1.
ICH0 (82801AB):
Data Parity Error Detected—RO. Hardwired to ‘0’.
7
Fast Back to Back—RO.
Hardwired to ‘1’ to indicate that the PCI to hub interface target logic is
capable of receiving fast back-to-back cycles.
6
User Definable Features (UDF) —RO. Hardwired to ‘0’.
5
66 MHz Capable—RO. Hardwired to ‘0’.
4:0
Reserved.