SMART Embedded Computing MVME2502, Installation And User Manual

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86 MVME2502 Installation and Use (6806800R96L)
Functional Description
Functional Description
4.9 PMC/XMC Sites
The MVME2502 hosts two PMC/XMC sites and accepts either a PMC or an XMC add-on
card. Only an XMC or a PMC may be populated at any given time as both occupy the same
physical space on the PCB. The MVME2502 does not support combination PMC/XMC
cards. The site provides a rear PMC I/O.
The PMC sites are fully compliant with the following:
1. VITA 39 –PCI-X for PMC.
2. VITA 35-2000 for PMC P4 to VME P2 Connection.
3. PCI Rev 2.2 for PCI Local Bus Specification.
4. PCI-X PT 2.0 for PCI-X Protocol Addendum to the PCI Local Bus Specs.
5. IEEE Standard P1386-2001 for Standard for Common Mezzanine Card Family.
6. IEEE Standard P1386.1-2001 for Standard Physical and Environmental Layer for PCI
Mezzanine Card.
7. VITA 42 for XMC.
8. VITA 42.3, PCIe for XMC.
PMC/XMC sites are keyed for 3.3V PMC signaling. The PMC and the XMC add-on cards
must have a hole in the 3.3 V PMC keying position in order to be populated on the
MVME2502 board. The XMC specification accommodates this since it is expected that
carrier cards will host both XMC and PMC capable add-on cards.
The MVME2502 have a keying pin at the 3.3V location at each PMC site. The MVME2502
boards are not 5 volt PMC IO compatible. The MVME2502 also has a 5 volt keying pin
location at each PMC site. At PMC site 2, the 5 volt keying pin hole is used to mount the
SATA adapter card. Warning label covers 5 volt keying pin at PMC site 1 and also at PMC
site 2. If 5 volt PMC or XMC devices are operated on MVME2502 it may cause damage to
the board.
The MVME2502 utilizes the P2020 x2 link PCI Express interface for PMC/XMC1 and x1
link PCI Express interface for PMC/XMC2. It is designed such that same PCI Express
interface is used for either PMC or XMC. It is made possible by using PCIe MUX/DEMUX
chip. The CPLD via on-board switch controls the enable pin.
The CPLD controls the PCIe MUX/DEMUX at both sites. The CPLD detects the presence
signal provided by the XMC or PMC board and it will be used to configure the routing of
PCIe MUX/DEMUX correspondingly.