Guppy PRO Technical Manual
V4.1.2
187
The configuration ROM is divided into
•
Bus info block: providing critical information about the bus-related
capabilities
•
Root directory: specifying the rest of the content and organization, such
as:
– Node unique ID leaf
– Unit directory
– Unit dependent information
The base address of the camera control register is calculated as follows based
on the camera-specific base address:
The entry with key 8D in the root directory (420h in this case) provides the
offset for the node unique ID leaf.
To compute the effective start address of the node unique ID leaf:
Bus info block
Offset 0 to 7
8 to 15 16 to 23 24 to 31
400h
04
29
0C
C0
404h
31
33
39
34
…. ASCII for 1394
408h
20
00
B2
03
…. Bus capabilities
40Ch
00
0A
47
01
….
Node_Vendor_Id
,
Chip_id_hi
410h
Serial number
…. Chip_id_lo
Root directory
414h
00
04
B7
85
According to IEEE1212, the root
directory may have another length. The
keys (e.g. 8D) point to the offset factors
rather than the offset (e.g. 420h) itself.
418h
03
00
0A
47
41Ch
0C
00
83
C0
420h
8D
00
00
02
424h
D1
00
00
04
Table 104: Configuration ROM
To compute the effective start address of the node unique ID leaf
currAddr
= node unique ID leaf address
destAddr
= address of directory entry
addrOffset = value of directory entry
destAddr
= cu (4 × addrOffset)
= 420h + (4 × 000002h)
= 428h
Table 105: Computing effective start address
