NHE6300ESB S L7XJ Intel, NHE6300ESB S L7XJ Datasheet - Page 197

• Manufacturer Part Number: NHE6300ESB S L7XJ
• Manufacturer: Intel

Specifications of NHE6300ESB S L7XJ

• Lead Free Status / RoHS Status: Compliant

5—Intel
5.17.2.2 Transfer Descriptors (TD)
Figure 18. Transfer Descriptor
Table 87.
November 2007
Order Number: 300641-004US
®
6300ESB ICH
Transfer Descriptors (TDs) express the characteristics of the transaction requested on
USB by a client. TDs are always aligned on 16-byte boundaries, and the elements of
the TD are shown in
a small number of control bits in the descriptor that the Intel
during operation. All Transfer Descriptors have the same basic, 32-byte structure.
During operation, the Intel
some fields of the TD. When a consistency check fails, the Intel
immediately and issues an interrupt to the system. This interrupt cannot be masked
within the Intel
TD Link Pointer
31:4
Bit
3
2
1
0
R = R e s e r v e d
31
R
ICH Read/Write
30
Link Pointer (LP): Bits [31:4] Correspond to memory address signals [31:4],
respectively. This field points to another TD or QH.
Reserved. Must be 0 when writing this field.
Depth/Breadth Select (VF): This bit is only valid for queued TDs and indicates to the
hardware whether it should process in a depth first or breadth first fashion. When set to
depth first, it informs the Intel
queue rather than starting a new queue.
0 = Breadth first
1 = Depth first
QH/TD Select (Q): This bit informs the Intel
referenced by the link pointer is another TD or a QH. This allows the Intel
ICH to perform the proper type of processing on the item after it is fetched.
0 = TD
1 = QH
Terminate (T): This bit informs the Intel
does not point to another valid entry. When encountered in a queue context, this bit
indicates to the Intel
A TD encountered outside of a queue context with the T bit set informs the Intel
6300ESB ICH that this is the last TD in the frame.
0 = Link Pointer field is valid.
1 = Link Pointer field not valid.
S P D
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28
C _ E R R
MaxLen
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6300ESB ICH.
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L S
Figure
25
I O
O
S
24
I O C
23
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®
18. The four different USB transfer types are supported by
6300ESB ICH hardware performs consistency checks on
6300ESB ICH that there are no more valid entries in the queue.
21
L i n k P o i n t e r
ICH Read Only
20
Status
R D
19
®
18
B u f f e r P o i n t e r
6300ESB ICH to process the next transaction in the
E n d P t
16
Description
15
®
14
6300ESB ICH that the link pointer in this TD
D e v i c e A d d r e s s
R
®
6300ESB ICH whether the item
11
10
8
Intel
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7
6300ESB ICH interprets
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A c t L e n
6300ESB I/O Controller Hub
6300ESB ICH halts
4
P I D
3
0
V f
2
Q
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1
6300ESB
T
0
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DS