NHE6300ESB S L7XJ Intel, NHE6300ESB S L7XJ Datasheet - Page 308

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

Specifications of NHE6300ESB S L7XJ

• Lead Free Status / RoHS Status: Compliant

7.1.29
Table 175. Offset 70h: MTT—Multi-Transaction Timer Register (HUB-PCI—
Intel
DS
308
Bits
Default Value:
7:3
2:0
®
6300ESB I/O Controller Hub
Note: Programming the MTT to a value of 00h disables this function, which could cause
Device:
Offset:
Multi-Transaction Timer
Count Value
Offset 70h: MTT—Multi-Transaction Timer
Register
(HUB-PCI—D30:F0)
MTT is an 8-bit register that controls the amount of time that the Intel
arbiter allows a PCI initiator to perform multiple back-to-back transactions on the PCI
bus. The Intel
Primary PCI bandwidth to an initiator that performs multiple back-to-back transactions
to fragmented memory ranges (and as a consequence it may not use long burst
transfers).
The number of clocks programmed in the MTT represents the ensured time slice
(measured in PCI clocks) allotted to the current agent, after which the arbiter will grant
another agent that is requesting the bus. The MTT value must be programmed with 8-
clock granularity in the same manner as MLT. For example, if the MTT is programmed to
18h, then the selected value corresponds to the time period of 24 PCI clocks.The
default value of MTT is 20h (32 PCI clocks).
starvation problems for some PCI master devices. Programming of the MTT to anything
less than 16 clocks will not allow the Grant-to-FRAME# latency to be 16 clocks. The
MTT timer will timeout before the Grant-to-FRAME# trigger causing a rearbitration.
D30:F0)
Reserved
30
70h
20h
Name
®
6300ESB ICH’s MTT mechanism is used to ensure a fair share of the
This field specifies the amount of time that grant will remain
asserted to a master continuously asserting its request for
multiple transfers. This field specifies the count in an 8-clock
(PCI clock) granularity.
Reserved.
Description
Attribute:
Function:
Size:
0
Read/Write
8-bit
Order Number: 300641-004US
Intel
®
®
6300ESB ICH’s
6300ESB ICH—7
November 2007
Access
R/W