User`s guide

Jumpers and Connectors • 21
2.2.3 JP2, JP3, JP4 and JP5 (COM2 RS-232/422/485/485+
Selectable) on RTM
As COM2 is RS-232/422/485 selectable, to operate in its different
communication protocols, JP2, JP3, JP4 and JP5 must be set according to
the table listed below. The numbers in the table indicate the pin number that
needs to be shorted together.
Setting JP2 JP3 JP4 JP5
RS-232
3-5
4-6
3-5
4-6
5-6 ----
RS-422
1-3
2-4
1-3
2-4
3-4
3-5
4-6
RS-485
1-3
2-4
1-3
2-4
1-2
3-5
4-6
RS-485+
1-3
2-4
1-3
2-4
1-2
1-3
2-4
Table 6: JP2, JP3, JP4 and JP5 Settings
2.2.4 PMC VIO Zero Ω Shorting Resistors
The cPCI-6765(A) contains two pairs of zero Ω shorting resistors that allow
the user to configure the PMC VIO voltage to either +5V or +3.3V. The PMC
interface is on the PCI Bus with PMC VIO default factory setting tied to +5.0V by
0-ohm resistors R33 and R34. If R33 and R34 are removed, and R38 and
R49 are installed with 0-ohm resistors, the PMC VIO is +3.3V. Refer to the
table below:
PMC VIO +5.0V +3.3V
R38, R49 Mount
R33, R34 Mount (Default)
Table 7: Zero Ω shorting resistor settings