Fujitsu P4X-0036-2M-800L Datasheet download pdf (Page 42)

Intel® Xeon™ Processor with 800 MHz System Bus

42 Datasheet

DBI[3:0]# I/O DBI[3:0]# are source synchronous and indicate the polarity of the D[63:0]# signals. The

DBI[3:0]# signals are activated when the data on the data bus is inverted. If more than

half the data bits, within a 16-bit group, would have been asserted electronically low, the

bus agent may invert the data bus signals for that particular sub-phase for that 16-bit

group.

DBSY# I/O DBSY# (Data Bus Busy) is asserted by the agent responsible for driving data on the

processor front side bus 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 all

processor front side bus agents.

DEFER# I 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 I/O agent. This signal must connect the appropriate pins of all processor front

side bus agents.

DP[3:0]# I/O 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.

DRDY# I/O 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 all processor front

side bus agents.

DSTBN[3:0]# I/O Data strobe used to latch in D[63:0]#. 4

DSTBP[3:0]# I/O Data strobe used to latch in D[63:0]#. 4

Table 20. Signal Definitions (Sheet 4 of 9)

Name Type Description Notes

DBI[3:0] Assignment To Data Bus

Bus Signal Data Bus Signals

DBI0# D[15:0]#

DBI1# D[31:16]#

DBI2# D[47:32]#

DBI3# D[63:48]#

Signals Associated Strobes

D[15:0]#, DBI0# DSTBN0#

D[31:16]#, DBI1# DSTBN1#

D[47:32]#, DBI2# DSTBN2#

D[63:48]#, DBI3# DSTBN3#

Signals Associated Strobes

D[15:0]#, DBI0# DSTBP0#

D[31:16]#, DBI1# DSTBP1#

D[47:32]#, DBI2# DSTBP2#

D[63:48]#, DBI3# DSTBP3#

1 2 ... 37 38 39 40 41 42 43 44 45 46 47 ... 95 96

No comments

Fujitsu P4X-0036-2M-800L Datasheet Page 42