Teknor Industrial Computers TEK-CPCI-1000, Техническое справочное руководство

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TEK-CPCI-1000 Technical Reference Manual
6-12
6.7.1 Connector Keying
The CompactPCI connector supports guide lugs located on the board (system board and
peripherals) and the backplane connectors to ensure a correct polarized mating. A proper
mating is enhanced by the use of coding keys for 3.3V and 5V operation.
Coding keys prevent inadvertent installation of a 5V board in a 3.3V slot. The TEK-CPCI-
1000 provides 3.3V signals. The PCI bus does not require to be keyed. Backplane
connectors must always be keyed according to the signaling level.
Coding Key Colors are defined as follows:
Signaling Voltage Key Color
3.3V Cadmium Yellow
5V Brilliant Blue
Universal board (5V and 3.3V) none
6.7.2 Bus Mastering
The TEK-CPCI-1000 provides four pairs of REQ/GNT arbitration signals. This means the
board is capable of interfacing up to four peripheral modules with PCI Bus Master
capabilities.
When connecting the board to a backplane, be aware that one REQ/GNT pair may be
already assigned to the onboard Ethernet feature.
CAUTION
With the onboard Ethernet enabled only three PCI Bus Master devices
are supported.