Intel Pga478 - P4-2ghz 512kb 400mhz Fsb, Техническое описание

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Intel
®
Celeron
®
Processor 1.66 GHz/1.83 GHz—Package Mechanical Specifications and Pin
Information
Intel
®
Celeron
®
Processor 1.66 GHz/1.83 GHz
DS January 2007
32 Order Number: 315876-002
D[63:0]#
Input/
Output
D[63:0]# (Data) are the data signals. These signals provide a 64-bit data path
between the FSB agents, and must connect the appropriate pins on both agents.
The data driver asserts DRDY# to indicate a valid data transfer.
D[63:0]# are quad-pumped signals and is thus be driven four times in a
common clock period. D[63:0]# are latched off the falling edge of both
DSTBP[3:0]# and DSTBN[3:0]#. Each group of 16 data signals correspond to a
pair of one DSTBP# and one DSTBN#. The following table shows the grouping of
data signals to data strobes and DINV#.
Furthermore, the DINV# pins determine the polarity of the data signals. Each
group of 16 data signals corresponds to one DINV# signal. When the DINV#
signal is active, the corresponding data group is inverted and therefore sampled
active high.
DBSY#
Input/
Output
DBSY# (Data Bus Busy) is asserted by the agent responsible for driving data on
the FSB to indicate that the data bus is in use. The data bus is released after
DBSY# is deasserted. This signal must connect the appropriate pins on both FSB
agents.
DEFER# Input
DEFER# is asserted by an agent to indicate that a transaction cannot be
guaranteed in-order completion. Assertion of DEFER# is normally the
responsibility of the addressed memory or Input/Output agent. This signal must
connect the appropriate pins of all FSB agents.
DP[3:0]#
Input/
Output
DP[3:0]# (Data Parity) provide parity protection for the D[63:0]# signals. They
are driven by the agent responsible for driving D[63:0]#, and must connect the
appropriate pins of all processor front side bus agents.
DINV[3:0]#
Input/
Output
DINV[3:0]# (Data Bus Inversion) are source synchronous and indicate the
polarity of the D[63:0]# signals. The DINV[3:0]# signals are activated when the
data on the data bus is inverted. The bus agent inverts the data bus signals if
more than half the bits, within the covered group, change level in the next cycle.
DRDY#
Input/
Output
DRDY# (Data Ready) is asserted by the data driver on each data transfer,
indicating valid data on the data bus. In a multi-common clock data transfer,
DRDY# may be deasserted to insert idle clocks. This signal must connect the
appropriate pins of both FSB agents.
Table 11. Signal Description (Sheet 3 of 7)
Name Type Description
Table 12. Quad-Pumped Signal Groups
Data Group
DSTBN#/
DSTBP#
DINV#
D[15:0]# 0 0
D[31:16]# 1 1
D[47:32]# 2 2
D[63:48]# 3 3
Table 13. DINV[3:0]# Assignment To Data Bus
Bus Signal Data Bus Signals
DINV[3]# D[63:48]#
DINV[2]# D[47:32]#
DINV[1]# D[31:16]#
DINV[0]# D[15:0]#