Signal Description
70 Datasheet, Volume 1
6.6 Direct Media Interface (DMI) Signals6.7 Phase Lock Loop (PLL) Signals6.8 Test Access Points (TAP) Signals

Table 6-8. Direct Media Interface (DMI) Sign als – Processor to PCH Serial Interface

Signal Name Description Direction/
Buffer Type
DMI_RX[3:0]
DMI_RX#[3:0] DMI Input from PCH: Direct Media Interface receive
differential pair. I
DMI
DMI_TX[3:0]
DMI_TX#[3:0] DMI Output to PCH: Direct Media Interface transmit
differential pair. O
DMI

Table 6-9. Phase Lock Loop (PLL) Signals

Signal Name Description Direction/
Buffer Type
BCLK
BCLK# Differential bus clock input to the processor I
Diff Clk

Table 6-10. Test Access Points (TAP) Signals

Signal Name Description Direction/
Buffer Type
BPM#[7:0]
Breakpoint and Performance Monitor Signals: These signals
are outputs from the processor that indicate the status of
breakpoints and programmable counters used for monitoring
processor performance.
I/O
CMOS
BCLK_ITP
BCLK_ITP# These signals are connected in parallel to the top side debug
probe to enable debug capacities. I
DBR#
DBR# is used only in systems where no debug port is
implemented on the system board. DBR# is used by a debug
port interposer so that an in-target probe can drive system
reset.
O
PRDY# PRDY# is a processor output used by debug tools to determine
processor debug readiness. O
Asynchronous
CMOS
PREQ# PREQ# is used by debug tools to request debug operation of the
processor. I
Asynchronous
CMOS
TCK Test Clock: This signal provides the clock input for the
processor Test Bus (also known as the Test Access Port). TCK
must be driven low or allowed to float during power on Reset.
I
CMOS
TDI Test Data In: This signal transfers serial test data into the
processor. TDI provides the serial input needed for JTAG
specification support.
I
CMOS
TDO Test Data Out: This signal transfers serial test data out of the
processor. TDO provides the serial output needed for JTAG
specification support.
O
Open Drain
TMS Test Mode Select: A JTAG specification support signal used by
debug tools. I
CMOS
TRST# Test Reset: This signal resets the Test Access Port (TAP) logic.
TRST# must be driven low during power on Reset. I
CMOS