IDT 89HPES12T3G2, Preliminary User'S Manual

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IDT PES12T3G2 Device Overview
PES12T3G2 User Manual 1 - 7 January 28, 2013
Notes
Signal Type Name/Description
CCLKDS I Common Clock Downstream. The assertion of this pin indicates that all
downstream ports are using the same clock source as that provided to
downstream devices.This bit is used as the initial value of the Slot Clock
Configuration bit in all of the Link Status Registers for downstream ports.
The value may be overridden by modifying the SCLK bit in each down-
stream port’s PCIELSTS register.
CCLKUS I Common Clock Upstream. The assertion of this pin indicates that the
upstream port is using the same clock source as the upstream device. This
bit is used as the initial value of the Slot Clock Configuration bit in the Link
Status Register for the upstream port. The value may be overridden by
modifying the SCLK bit in the P0_PCIELSTS register.
MSMBSMODE I Master SMBus Slow Mode. The assertion of this pin indicates that the
master SMBus should operate at 100 KHz instead of 400 KHz. This value
may not be overridden.
PERSTN I Fundamental Reset. Assertion of this signal resets all logic inside
PES12T3G2 and initiates a PCI Express fundamental reset.
RSTHALT I Reset Halt. When this signal is asserted during a PCI Express fundamental
reset, PES12T3G2 executes the reset procedure and remains in a reset
state with the Master and Slave SMBuses active. This allows software to
read and write registers internal to the device before normal device opera-
tion begins. The device exits the reset state when the RSTHALT bit is
cleared in the SWCTL register by an SMBus master.
SWMODE[2:0] I Switch Mode. These configuration pins determine the PES12T3G2 switch
operating mode.
0x0 - Normal switch mode
0x1 - Normal switch mode with Serial EEPROM initialization
0x2 - through 0x7 Reserved
These pins should be static and not change following the negation of
PERSTN.
Table 1.6 System Pins
Signal Type Name/Description
JTAG_TCK I JTAG Clock. This is an input test clock used to clock the shifting of data
into or out of the boundary scan logic or JTAG Controller. JTAG_TCK is
independent of the system clock with a nominal 50% duty cycle.
JTAG_TDI I JTAG Data Input. This is the serial data input to the boundary scan logic or
JTAG Controller.
Table 1.7 Test Pins (Part 1 of 2)