PCI-to-PCI Bridges
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PCI-to-PCI Bridges
The MVME5500 uses a PCI 2.1 compliant, 66 MHz capable, HiNT
PCI 6154 PCI-to-PCI bridge. The primary side connects to PCI Bus 0.0 of
the GT-64260B and PMC/IPMC slot 1. The secondary side connects to
PCI Bus 0.1 on which a PMC expansion connector and the VME controller
resides.
PMC Sites
The MVME5500 board supports two PMC sites. Both sites support
processor PMC boards with two IDSELs and two arbitration request/grant
pairs. Slot 1 is connected to PCI Bus 0.0 of the GT-64260B and is 66 MHz
capable. Slot 2 is connected to PCI Bus 1.0 of the GT-64260B and is also
66 MHz capable.
Note
If a PMC module is plugged into PMC slot 1, the memory
mezzanine card cannot be used because the PMC module covers
the memory mezzanine connector.
PCI IDSEL Definition
PCI device configuration registers are accessed by using the IDSEL signal
of each PCI agent to an A/D signal as defined in the Peripheral Component
Interconnect (PCI) Local Bus Specification, Revision 2.2. IDSEL
definitions for the MVME5500 are shown in the MVME5500 Single-Board
Computer Programmer’s Reference Guide.
PCI Bus Arbitration
PCI arbitration for the MVME5500 PCI Buses 0.0 and 1.0 is provided by
an external arbiter PLD. The arbiter PLD implements a round-robin
priority algorithm. PCI arbitration for PCI Bus 0.1 is provided by the HiNT
PCI 6154 secondary internal arbiter.