cPCI-DMXS64GX Technical Reference Manual
3.4.7. Connector Keying
CompactPCI connector support guide lugs to ensure a correct polarized mating. A proper
mating is enhanced by the use of color coded keys for 3.3V and 5V operation.
Color coded keys prevent inadvertent installation of a 5V peripheral board in a 3.3V slot.
The cPCI-DMXS64GX is universal. It does not support coding key. The PCI bus does not
require to be keyed. Backplane connectors must always be keyed according to the signaling
(VIO) level.
Coding Key Colors are defined as follows:
Signaling Voltage
Universal board (5V and 3.3V)
3.3V
5V
-48V
3.28
Key Color
Cadmium Yellow
Brilliant Blue
none
Red