DP83815
2.0 Pin Description
(Continued)
PCI Bus Interface
Symbol
PERRN
LQFP Pin
No(s)
97
LBGA Pin
No(s)
N9
Dir
I/O
Description
Parity Error:
The DP83815 as a master or target will assert this
signal low to indicate a parity error on any incoming data (except for
special cycles). As a bus master, it will monitor this signal on all write
operations (except for special cycles).
Request:
The DP83815 will assert this signal low to request
ownership of the bus from the central arbiter.
Reset:
When this signal is asserted all outputs of DP83815 will be
tri-stated and the device will be put into a known state.
System Error:
This signal is asserted low by DP83815 during
address parity errors and system errors if enabled.
Stop:
This signal is asserted low by the target device to request the
master device to stop the current transaction.
Target Ready:
As a master, this signal indicates that the target is
ready for the data during write operation and with the data during
read operation. As a target, this signal will be asserted low when the
(target) device is ready to complete the current data phase
transaction. This signal is used in conjunction with the IRDYN signal.
Data transaction takes place at the rising edge of PCICLK when both
IRDYN and TRDYN are asserted low.
Power Management Event/Clock Run Function:
This pin is a dual
function pin. The function of this pin is determined by the
CLKRUN_EN bit 0 of the CLKRUN Control and Status register
(CCSR). Default operation of this pin is PMEN.
Power Management Event:
This signal is asserted low by DP83815
to indicate that a power management event has occurred. For pin
connection please refer to Section 6.7.
Clock Run Function:
In this mode, this pin is used to indicate when
the PCICLK will be stopped.
3VAUX
122
J11
I
PCI Auxiliary Voltage Sense:
This pin is used to sense the
presence of a 3.3V auxiliary supply in order to define the PME
Support available. For pin connection please refer to Section 6.7.
This pin has an internal weak pull down.
PWRGOOD
123
H13
I
PCI bus power good:
Connected to PCI bus 3.3V power (not
3.3Vaux), this pin is used to sense the presence of PCI bus power.
This pin has an internal weak pull down.
REQN
64
J4
O
RSTN
62
J3
I
SERRN
98
L9
I/O
STOPN
96
M9
I/O
TRDYN
93
N8
I/O
PMEN/
CLKRUNN
59
H2
I/O
7
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