XIO2000AI TAOS [TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS], XIO2000AI Datasheet - Page 48

• Manufacturer Part Number: XIO2000AI
• Description: PCI Express to PCI Bus Translation Bridge
• Manufacturer: TAOS [TEXAS ADVANCED OPTOELECTRONIC SOLUTIONS]

Feature/Protocol Descriptions
3.7
38
31
SCPS155C
In addition, the bridge converts the destination ID device number to one of the AD[31:16] lines as the IDSEL
signal. The implemented IDSEL signal mapping is shown in Table 3−11.
Type 1 configuration registers transactions that target a downstream bus other then the secondary bus are
output on the PCI bus as type 1 PCI configuration transactions. Figure 3−7 shows the address phase of a type
1 configuration transaction on the PCI bus as defined by the PCI specification.
PCI Interrupt Conversion to PCI Express Messages
The bridge converts interrupts from the PCI bus sideband interrupt signals to PCI Express interrupt messages.
PCI Express Assert_INTx messages are generated when one of the PCI bus INT[A:D] input terminals
transitions low. The requester ID portion of the Assert_INTx message uses the value stored in the primary bus
number register (see Section 4.11) as the bus number, 0 as the device number, and 0 as the function number.
The tag field for each Assert_INTx message is 00h. The lower two bits in the code field indicate the asserted
interrupt signal.
PCI Express Deassert_INTx messages are generated when one of the PCI bus INT[A:D] input terminals
transitions high. The requester ID portion of the Deassert_INTx message uses the value stored in the primary
bus number register as the bus number, 0 as the device number, and 0 as the function number. The Tag field
for each Deassert_INTx message is 00h. The lower two bits in the code field indicate the deasserted interrupt
signal.
Table 3−12, Figure 3−8, and Figure 3−9 illustrate the format for both the assert and deassert INTx messages.
Reserved
Figure 3−7. Type 1 Configuration Transaction Address Phase Encoding
24
Table 3−11. Type 0 Configuration Transaction IDSEL Mapping
23
Bus Number
NUMBER
DEVICE
00000
00001
00010
00100
00101
01000
01001
01010
00011
00110
00111
01011
01100
01101
01110
01111
1xxxx
16
0000 0000 0000 0001
0000 0000 0000 0010
0000 0000 0000 0100
0000 0000 0000 1000
0000 0000 0001 0000
0000 0000 0010 0000
0000 0000 0100 0000
0000 0000 1000 0000
0000 0001 0000 0000
0000 0010 0000 0000
0000 0100 0000 0000
0000 1000 0000 0000
0001 0000 0000 0000
0010 0000 0000 0000
0100 0000 0000 0000
1000 0000 0000 0000
0000 0000 0000 0000
15
AD[31:16]
Device Number
11
10
Function
Number
8
7
April 2007 Revised October 2008
Register Number
2
1
0
0
1