3-17
BUS OVERVIEW
The Extended Functions, EXF[4:0]#, supported are listed in Table 3-11.
EXF4# (SMM Memory) is asserted by the Pentium Pro processor if the processor is in System
Management Mode and indicates that the processor is accessing a separate “shadow” memory,
the SMRAM. Each memory or I/O agent must observe this signal and only accept a transaction
involving SMRAM if the agent provides the SMRAM.
EXF3# (Split Lock) is asserted to indicate that a locked operation is split across 32-byte bound-
aries for writeback memory or 8-byte boundaries for uncacheable memory. Note that SPLCK#
is asserted for the first transaction in a locked operation only.
EXF1# is asserted if the transaction can be deferred by the responding agent. EXF1# is always
deasserted for the transactions in a locked operation, deferred reply transactions, and bus Write-
back Line transactions.
Table 3-10. Special Transaction Encoding on Byte Enables
Special Transaction
Byte Enables[7:0]#
Shutdown
0000 0001
Flush
0000 0010
Halt
0000 0011
Sync
0000 0100
Flush Acknowledge
0000 0101
Stop Grant Acknowledge
0000 0110
SMI Acknowledge
0000 0111
Reserved
all other encodings
Table 3-11. Extended Function Pins
Extended Function Pin
Extended Function Signal
Function
EXF4#
SMMEM#
Accessing SMRAM space
EXF3#
SPLCK#
Split Lock
EXF2#
Reserved
EXF1#
DEN#
Defer Enable
EXF0#
Reserved
Summary of Contents for Pentium Pro Family
Page 17: ...1 Component Introduction ...
Page 26: ...2 Pentium Pro Processor Architecture Overview ...
Page 27: ......
Page 36: ...3 Bus Overview ...
Page 62: ...4 Bus Protocol ...
Page 105: ...5 Bus Transactions and Operations ...
Page 126: ...6 Range Registers ...
Page 131: ...7 Cache Protocol ...
Page 135: ...8 Data Integrity ...
Page 148: ...9 Configuration ...
Page 161: ...10 Pentium Pro Processor Test Access Port TAP ...
Page 172: ...11 Electrical Specifications ...
Page 201: ...12 GTL Interface Specification ...
Page 229: ...13 3 3V Tolerant Signal Quality Specifications ...
Page 233: ...14 Thermal Specifications ...
Page 239: ...15 Mechanical Specifications ...
Page 241: ...15 2 MECHANICAL SPECIFICATIONS s Figure 15 1 Package Dimensions Bottom View ...
Page 252: ...16 Tools ...
Page 260: ...16 8 TOOLS Figure 16 4 Generic MP System Layout for Debug Port Connection ...
Page 264: ...17 OverDrive Processor Socket Specification ...
Page 290: ...A Signals Reference ...
Page 320: ...Index ...
Page 328: ......