Signal Ball Description
PLX Technology, Inc.
Table 3-4. PEX 8532 Hot Plug Signals – 72 Balls (Cont.)
Signal Name
Type
Location
Description
Combination of Hot Plug PRSNT1# and PRSNT2# Input
for Station 0 Ports (4 Balls)
Active-Low input connected to the slot’s PRSNT2# signal, which on the add-in
board connects to the slot’s PRSNT1# signal, which is normally grounded on
the PRSNT2# signal at the motherboard slot. A change in the HP_PRSNTx#
Input signal state is latched in the Slot Status register Presence Detect
Changed bit (offset 80h[19]), and the state change can assert an interrupt
to notify the Host of board presence or absence.
When the following conditions exist:
I
P34, AC34,
R1, AD1
HP_PRSNT[3:0]#
PUa
•
HP_PRSNTx# is not masked (Slot Control register Presence Detect
Changed Enable bit (offset 80h[3]=1), and
Slot Control register Hot Plug Interrupt Enable bit is set
(offset 80h[5]=1),
•
an interrupt (MSI, or INTx message, both mutually exclusive) can be
generated.
Note: HP_PRSNTx# is internally de-bounced, but must remain stable for
at least 10 ms.
Combination of Hot Plug PRSNT1# and PRSNT2# Input
for Station 1 Ports (4 Balls)
Refer to description for HP_PRSNT[3:0]#.
I
AA33, M33,
AB2, N2
HP_PRSNT[11:8]#
PUa
Active-Low Hot Plug Power Enable Output for Station 0 Ports (4 Balls)
Active-Low Slot Control Logic output that controls the slot power state.
When this signal is Low, power is enabled to the slot.
Enabled when the Slot Capabilities register Power Controller Present bit
is set (offset 7Ch[1]=1).
When software turns the slot’s Power Controller On or Off (Slot Control
register Power Controller Control bit, offset 80h[10]), a Command
Completed interrupt can be generated to notify the Host that the command
has been executed.
When the following conditions exist:
N34, AB34,
P1, AC1
HP_PWREN[3:0]#
O
•
Slot Control register Command Completed Interrupt Enable bit
is not masked (offset 80h[4]=1), and
•
Slot Control register Hot Plug Interrupt Enable bit is set
(offset 80h[5]=1),
an interrupt (MSI, or INTx message, both mutually exclusive) can be generated
to the Host.
When HP_MRLx# is enabled [Slot Capabilities register MRL Sensor Present
bit is set (offset 7Ch[2]=1)], HP_MRLx# input assertion enables Hot Plug
output sequencing to turn On the slot’s power, by asserting HP_PWRENx#
after reset or under software control.
Active-Low Hot Plug Power Enable Output for Station 1 Ports (4 Balls)
Refer to description for HP_PWREN[3:0]#.
AB33, N33,
AC2, P2
HP_PWREN[11:8]#
O
22
ExpressLane PEX 8532AA/BA/BB/BC 8-Port/32-Lane Versatile PCI Express Switch Data Book
Copyright © 2007 by PLX Technology, Inc. All Rights Reserved – Version 1.6
PLX [ PLX TECHNOLOGY ]
