Motorola MPC8260 - Manual (Page 211)

MOTOROLA Chapter 6. External Signals 6-9
Part III. The Hardware Interface
L_A15
SMI
PCI_FRAME
Local bus address 15ÑLocal bus address bit 15 output pin. In the local address bus bit 14 is most
signiÞcant and bit 31 is least signiÞcant.
System management interruptÑSystem management interrupt input to the core.
PCI frameÑPCI cycle frame input output pin. Used by the current PCI master to indicate the
beginning and duration of an access. Driven by the MPC8260 when its PCI interface is the master
of the access. Otherwise, it is an input.
L_A16
PCI_TRDY
Local bus address 16ÑLocal bus address bit 16 output pin. In the local address bus bit 14 is most
signiÞcant and bit 31 is least signiÞcant.
PCI target readyÑPCI target ready input/output pin. This pin is driven by the MPC8260 when its
PCI interface is the target of a PCI transfer. Assertion of this pin indicates that the PCI target is
ready to send or accept a data beat.
L_A17
PCI_IRDY
CKSTOP_OUT
Local bus address 17ÑLocal bus address bit 17 output pin. In the local address bus bit 14 is most
signiÞcant and bit 31 is least signiÞcant.
PCI initiator readyÑPCI initiator ready input/output pin. This pin is driven by the MPC8260 when its
PCI interface is the initiator of a PCI transfer. Assertion of this pin indicates that the PCI initiator is
ready to send or accept a data beat.
Checkstop outputÑ(Output) Assertion of CKSTOP_OUT indicates the core is in checkstop mode.
L_A18
PCI_STOP
Local bus address 18ÑLocal bus address bit 18 output pin. In the local address bus bit 14 is most
signiÞcant and bit 31 is least signiÞcant.
PCI stopÑPCI stop input/output pin. This pin is driven by the MPC8260 when its PCI interface is
the target of a PCI transfer. Assertion of this pin indicates that the PCI target is requesting the
master to stop the current PCI transfer.
L_A19
PCI_DEVSEL
Local bus address 19ÑLocal bus address bit 19 output pin. In the local address bus bit 14 is most
signiÞcant and bit 31 is least signiÞcant.
PCI device selectÑPCI device select input/output pin. This pin is driven by the MPC8260 when its
PCI interface has decoded the address as the target of the current PCI transfer. As an input,
PCI_DEVSEL indicates whether any device on the PCI bus has been selected.
L_A20
PCI_IDSEL
Local bus address 20ÑLocal bus address bit 20 output pin. In the local address bus bit 14 is most
signiÞcant and bit 31 is least signiÞcant.
PCI initialization device selectÑ(Input). Used to select MPC8260Õs PCI interface during a PCI
conÞguration cycle.
L_A21
PCI_PERR
Local bus address 21ÑLocal bus address bit 21 output pin. In the local address bus bit 14 is most
signiÞcant and bit 31 is least signiÞcant.
PCI parity errorÑPCI data parity error input/output pin. Assertion of this pin indicates that a data
parity error was detected during a PCI transfer (except for a special cycle).
L_A22
PCI_SERR
Local bus address 22ÑLocal bus address bit 22 output pin. In the local address bus bit 14 is most
signiÞcant and bit 31 is least signiÞcant.
PCI system errorÑPCI system error input/output pin. Assertion of this pin indicates that a PCI
system error was detected during a PCI transfer. The PCI system error is for reporting address
parity errors, data parity errors on a special cycle command, or other catastrophic system errors.
L_A23
PCI_REQ0
Local bus address 23ÑLocal bus address bit 23 output pin. In the local address bus bit 14 is most
signiÞcant and bit 31 is least signiÞcant.
PCI arbiter request 0ÑPCI request 0 input/output pin. When MPC8260Õs internal PCI arbiter is
used, this is an input pin. In this mode assertion of this pin indicates that an external PCI agent is
requesting the PCI bus. When an external PCI arbiter is used, this is an output pin. In this mode
assertion of this pin indicates that MPC8260Õs PCI interface is requesting the PCI bus.
Table 6-1. External Signals (Continued)
Signal Description