4-40
BUS PROTOCOL
In the example, the data transfer only takes one clock, so DBSY# is not asserted.
Write Partial Transactions are driven at full speed. The first transaction occurs on an idle bus and
looks just like the simple write case in Figure 4-18. TRDY# is driven 3 clocks later in T4. The
Normal No Data response is driven in T7 after inactive HITM# sampled in T6 indicates no im-
plicit writeback. TRDY# is observed active and DBSY# is observed inactive in T5. Therefore
the data transfer can begin in T6 as indicated by DRDY# assertion.
The TRDY# for transaction 2 must wait until the response for transaction 1 is sampled. TRDY#
is asserted the cycle after RS[2:0]# is sampled. Because the snoop results for transaction 2 have
been observed in T9, the response may be driven on RS[2:0]# in T10. TRDY# is sampled with
DBSY# deasserted in T10 and data is driven in T11.
There are no bottlenecks to maintaining this steady state.
4.6.2.8.
FULL SPEED WRITE LINE TRANSACTIONS (SAME AGENTS)
Figure 4-25 shows the steady-state behavior of the bus with full speed Write Line Transactions
with data transfers from the same request agent to the same addressed agent.Data transfers may
occur without a turn-around cycle only if from the same agent.
Figure 4-24. Full Speed Write Partial Transactions
CLK
ADS#
2
1
4
3
8
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5
{REQUEST}
DBSY#
D[63:0]#
DRDY#
HIT#
TRDY#
RS[2:0]#
10
9
12
11
16
15
14
13
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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: ......