78 Software Developer’s Manual

PCI Local Bus Interface

Table 4-4. Status Register Layout

40b
Memory Write and Invalidate Enable (not
applicable to the 82547GI/EI).
50b Palette Snoop Enable.
60b
Parity Error Response (not applicable to the
82547GI/EI).
70b Wait Cycle Enable.
8 0b SERR# Enable (not applicable to the 82547GI/EI).
90b Fast Back-to-Back Enable.
10a0b Interrupt Disable (INTA# or CSA signaled).
15:10
15:11a0b Reserved.
a. 82541xx and 82547GI/EI only.
Bit(s) Initial Value Description
15 4 3 0
Status Bits Reserved
Bit(s) Initial Value Description
3:0
2:0a0b Reserved.
3a0b
Interrupt Status. This bit is 1b when the Ethernet
controller is generating an interrupt internally.
When Interrupt Disable in the Command Register
is also cleared, the Ethernet controller asserts
INTA# or signal an interrupt over CSA.
41b
New Capabilities: Indicates that an Ethernet
controller implements Extended Capabilities. The
Ethernet controller sets this bit and implements a
capabilities list to indicate that it supports PCI
Power Management, PCI-X Bus, and message
signaled interrupts.
5 1b 66 MHz Capable (don’t care for the 82547GI/EI).
60b UDF Supported. Hardwired to 0b for PCI 2.3a.
70b
Fast Back-to-Back CapableThis bit must be
cleared to 0b in PCI-X mode (not applicable to the
82547GI/EI).
8 0b Data Parity Reported.
10:9 01b DEVSEL Timing (indicates medium device). Not
applicable to the 82547GI/EI.
11 0b Signaled Target Abort.