Gigabit LAN Configuration Registers
12.1.3
PCICMD—PCI Command Register
(Gigabit LAN—D25:F0)
Address Offset: 04h–05h
Attribute:
Size:
R/W, RO
16 bits
Default Value:
0000h
Bit
Description
15:11 Reserved
Interrupt Disable — R/W. This disables pin-based INTx# interrupts on enabled Hot-
Plug and power management events. This bit has no effect on MSI operation.
0 = Internal INTx# messages are generated if there is an interrupt for Hot-Plug or
power management and MSI is not enabled.
10
1 = Internal INTx# messages will not be generated.
This bit does not affect interrupt forwarding from devices connected to the root port.
Assert_INTx and Deassert_INTx messages will still be forwarded to the internal
interrupt controllers if this bit is set.
9
8
7
6
Fast Back to Back Enable (FBE) — RO. Hardwired to 0.
SERR# Enable (SEE) — R/W.
0 = Disable
1 = Enables the Gb LAN controller to generate an SERR# message when PSTS.SSE is
set.
Wait Cycle Control (WCC) — RO. Hardwired to 0.
Parity Error Response (PER) — R/W.
0 = Disable.
1 = Indicates that the device is capable of reporting parity errors as a master on the
backbone.
5
4
3
Palette Snoop Enable (PSE) — RO. Hardwired to 0.
Postable Memory Write Enable (PMWE) — RO. Hardwired to 0.
Special Cycle Enable (SCE) — RO. Hardwired to 0.
Bus Master Enable (BME) — R/W.
0 = Disable. All cycles from the device are master aborted
1 = Enable. Allows the root port to forward cycles onto the backbone from a Gigabit
LAN* device.
2
1
Memory Space Enable (MSE) — R/W.
0 = Disable. Memory cycles within the range specified by the memory base and limit
registers are master aborted on the backbone.
1 = Enable. Allows memory cycles within the range specified by the memory base and
limit registers can be forwarded to the Gigabit LAN device.
I/O Space Enable (IOSE) — R/W. This bit controls access to the I/O space registers.
0 = Disable. I/O cycles within the range specified by the I/O base and limit registers
are master aborted on the backbone.
0
1 = Enable. Allows I/O cycles within the range specified by the I/O base and limit
registers can be forwarded to the Gigabit LAN device.
Datasheet
373