The Unabridged Pentium 4 IA32 Processor Genealogy

Cautionary Note

Unless noted otherwise, the representation of all signal states in tables is in logical, not electrical format. As an example, the first row in Table 49-5 on page 1216 shows a 00000b on REQ[4:0]#, indicating a Deferred Reply transaction type. This means that REQ[4:0]# are deasserted (electrical ones) when driven onto REQ[4:0]#.

Table 49-5. Request Types (note: 0 = signal deasserted, 1 = signal asserted)

Packet A (Request)					Packet B (Extended Request)					Request Type
REQ4#	REQ3#	REQ2#	REQ1#	REQ0#	REQ4#	REQ3#	REQ2#	REQ1#	REQ0#
0	0	0	0	0	x	x	x	x	x	Deferred Reply. Initiated by Response Agent to complete a request received earlier. For more information, see “Pentium® 4 FSB Transaction Deferral” on page 1277.
0	0	0	0	1						Reserved (ignore).
0	1	0	0	0	DSZ field. Always 00b (= ...