7 configuration rom header register, 8 bus identification register – Texas Instruments Dual/Single Socket CardBus and UntraMedia Controller PCI7621 User Manual
Page 188
8−8
8.7
Configuration ROM Header Register
The configuration ROM header register externally maps to the first quadlet of the 1394 configuration ROM, offset
FFFF F000 0400h. See Table 8−6 for a complete description of the register contents.
Bit
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Name
Configuration ROM header
Type
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
Default
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Name
Configuration ROM header
Type
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
RW
Default
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Register:
Configuration ROM header
Offset:
18h
Type:
Read/Write
Default:
0000 XXXXh
Table 8−6. Configuration ROM Header Register Description
BIT
FIELD NAME
TYPE
DESCRIPTION
31−24
info_length
RW
IEEE 1394 bus-management field. Must be valid when bit 17 (linkEnable) in the host controller control
register at OHCI offset 50h/54h (see Section 8.16) is set to 1. The default value for this field is 00h.
23−16
crc_length
RW
IEEE 1394 bus-management field. Must be valid when bit 17 (linkEnable) in the host controller control
register at OHCI offset 50h/54h (see Section 8.16) is set to 1. The default value for this field is 00h.
15−0
rom_crc_value
RW
IEEE 1394 bus-management field. Must be valid at any time bit 17 (linkEnable) in the host controller
control register at OHCI offset 50h/54h (see Section 8.16) is set to 1.
8.8
Bus Identification Register
The bus identification register externally maps to the first quadlet in the Bus_Info_Block and contains the constant
3133 3934h, which is the ASCII value of 1394.
Bit
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
Name
Bus identification
Type
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
Default
0
0
1
1
0
0
0
1
0
0
1
1
0
0
1
1
Bit
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Name
Bus identification
Type
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
R
Default
0
0
1
1
1
0
0
1
0
0
1
1
0
1
0
0
Register:
Bus identification
Offset:
1Ch
Type:
Read-only
Default:
3133 3934h