12. Register Descriptions
358
PowerSpan II User Manual
80A1010_MA001_09
Integrated Device Technology
www.idt.com
IPL
R
PRI_RST
0
Inbound Post List
Indicates status of the Inbound Post List FIFO. If this bit
is set, there are Inbound Message Frames for the IOP
to process.
0 = empty
1 = not empty
XI
2
O_EN
R/W
PRI_RST
0
Extended MFA Enabled
The IOP programs this bit to enable the PowerSpan II
I
2
O Extended Capabilities support for the Outbound
Option. The Host Outbound Index Offset Register
needs to be programmed with the offset in the PCI I2O
target Image where the Host Outbound Index Register
can be located for the Outbound Option Support. This
can be accomplished through the Host Outbound Index
Alias register.
The IOP will need to program the following registers to
support I
2
O extended capabilities:
• I2O IOP Outbound Index register
• I2O Host Outbound Index Offset register
• I2O Host Outbound Index Alias register
I
2
O_EN
R/W
PRI_RST
0
I
2
O Enabled
The local processor sets this bit to enable the
PowerSpan II I2O Shell Interface support. The IOP
must initialize the I2O Inbound Free list and Post list
FIFO’s before enabling the PowerSpan II I2O Shell
Interface. When this bit is cleared, all
Image Base Address Register” on page 257
accesses
on Primary PCI are retried.
0 = I2O disabled
1 = I2O enabled
I
Name
Type
Reset
By
Reset
State
Function