3. Processor Bus Interface
90
PowerSpan II User Manual
80A1010_MA001_09
Integrated Device Technology
www.idt.com
For example, if TADDR[19:0] = 0x12345 and the BS bit in the PB_SIx_CTL register equals 0
(4-Kbyte image) and the address on the processor bus is PB_A[0:31] = 0x78563412, then the PCI
address becomes 0x12345412.
summarizes the relationship between translation offset,
processor bus address, and block size of the image.
Table 14: Translation Address Mapping
PB_SIx_TADDR
Processor Bus Address (PB_A)
BS bit
(PB_SIx_CTL register)
Block Size
31
0
10011
2G
31:30
0:1
10010
1G
31:29
0:2
10001
512M
31:28
0:3
10000
256M
31:27
0:4
01111
128M
31:26
0:5
01110
64M
31:25
0:6
01101
32M
31:24
0:7
01100
16M
31:23
0:8
01011
8M
31:22
0:9
01010
4M
31:21
0:10
01001
2M
31:20
0:11
01000
1M
31:19
0:12
00111
512k
31:18
0:13
00110
256k
31:17
0:14
00101
128k
31:16
0:15
00100
64k
31:15
0:16
00011
32k
31:14
0:17
00010
16k
31:13
0:18
00001
8k
31:12
0:19
00000
4k