3.5 Jumpers
The jumpers are located on the printed circuit board of the PRM4 device. By altering
the state of the jumpers, the serial interface on DB9 port can be set.
Serial interface
State
Jumpers
RS-232C
1-2
J3, J4, J5, J6, J10
2-3
RS-485 2-wire, no
termination
1-2
J11, J8
2-3
RS-485 2-wire, 120Ω
termination
1-2
J11
2-3
RS-422/485 4-wire,
no termination
1-2
J8, J9
2-3
RS-422/485 4-wire, R
termination 120Ω
1-2
J8
2-3
RS-422/485 4-wire,
T termination 120Ω
1-2
J9
2-3
RS-422/485 4-wire, T
and R- termination 120Ω
1-2
2-3
The following figure illustrates the device's circuit board with the layout of the
jumpers.
The jumpers J1 and J2 are used to set the device into the firmware upgrade mode.
Otherwise, they ought to be in 2-3 state.
The layout of the jumpers on the printed circuit board
Radio modem PRM4 868MHz /User's manual V1.6 / 24.05.2011
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