TSI350 Datasheet, PDF (102/163 Pages) Integrated Device Technology – This chapter discusses the following

102
13. Signals and Pinout > Signals
Table 23: Tsi350 Miscellaneous Signals
Signal Name
P_M66EN
S_M66EN
BPCCE
GPIO[3:0]/
HS_SWITCH_b
HS_ENUM_b
HS_LED
MS1, MS0
Type
I
I/OD
I
TS
O
O
I
Description
Primary Bus: 66MHz Enable
This signal indicates the operating speed of the primary interface in PCI mode. When pulled
high, the primary interface operates at 66 MHz. When pulled low, the primary interface
operates at 33 MHz.
Secondary Bus: 66MHz Enable
This signal is Wire OR input of all the M66EN signals driven by secondary devices. The
system operates at 66 MHz PCI, if this signal is pulled high. If the P_M66EN is tied low the
bridge drives the S_M66EN low during reset.
Bus/power clock control management pin
When signal BPCCE is tied high, and when Tsi350 is placed in the D3hot power state, it
enables Tsi350 to place the secondary bus in the B2 power state. Tsi350 disables the
secondary clocks and drives them to 0. When tied low, placing Tsi350 in the D3 hot power
state has no effect on the secondary bus clocks.
General Purpose Input Output
The GPIOs are programmable input and output signals. The Tsi350 supports four GPIOs,
which are independently controlled by software through the GPIO Output Enable control
register, GPIO Output Data Register and GPIO Input Data register. Each GPIO can be
programmed as input or output.
General-purpose I/O terminal GPIO[3] is HS_SWITCH_b in CompactPCI mode.
HS_SWITCH_b provides the status of the ejector handle switch to the CompactPCI logic.
Primary Bus: Hot Swap ENUM (PQFP package only)
The Hot Swap ENUM is used when the bridge is configured for cPCI Hot Swap support. This
pin is driven low when the bridge detects an event on HS_SWITCH_b, switch handle,
indicating board insertion or extraction event by the user. This output interrupts the host for
immediate attention.
Primary Bus: Compact PCI Hot Swap LED Output (PQFP package only)
The signal is used to illuminate the Hot Swap Status LED associated with the board. The
system software writes to LED bit in the Hot-Swap Control Status Register to control the LED
status.
If 0 = status LED is OFF
If 1 = status LED is ON.
Mode Select Inputs
These inputs are used to configure the bridge device for different modes of operation. The
following summarizes the modes.
MS0 = 0, MS1 = 1, Mode: Compact PCI hot-swap friendly PCI Bus PM Interface Specification
(Rev. 1.1), GPIO[3] functions as HS_SWITCH_b
MS0 =1, MS1= X, Mode: Compact PCI hot-swap disabled PCI Bus PM Interface Specification
(Rev. 1.1), GPIO[3] functions as GPIO[3]
MS0 =0, MS1= X, Mode: Compact PCI hot-swap disabled PCI Bus PM Interface Specification
(Rev. 1.1), GPIO[3] functions as GPIO[3]
Tsi350 User Manual
January 10, 2014
Integrated Device Technology
www.idt.com