20
© Sealevel Systems, Inc.
R5120 & R5140 Manual | SL9212 10/2021
Technical Description, Continued
Jumper Descriptions & Locations
The R5100 has jumpers on the motherboard for configuring the COM1 serial port and CompactFlash settings. In
rare instances where an incorrect setting is saved in the Setup Utility, you can use a jumper to clear the CMOS
memory.
The jumpers are located on the top side of the motherboard, under the large heat sink on top of the enclosure.
The PCI Express backplane jumper is located on the backplane, which can be accessed under the heat sink.
To access the jumpers, remove the eight (8) screws from the top of the heat sink. Remove the heat sink by lifting
straight up (it may seem hard to remove due to the thermal pads connecting internal heat sinks to external heat
sink). For the COM jumpers located at the corner of the motherboard, removing the side panels and the heat sink
will make access to these jumpers easier.
The jumpers can be found in the following locations.
Jumper Descriptions
Label
Description
J1
COM1 DCD and RI Voltage Selection
J2
COM1 RS-232/422/485 Configuration
J3
COM1 RS-232/422/485 Configuration
J4
COM1 RS-232/422/485 Configuration
J6
CompactFlash Master/Slave Setting
J7
Clear CMOS
J8
CompactFlash Voltage Setting
J1 (Backplane)
PCI Express Backplane Setting
(J1) COM1 DCD and RI Voltage Selection
Use the jumper (J1) to configure the voltage for DCD and RI.
