Acer Altos R700 Series, Service Manual

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Chapter 5 82
Rear RJ45 Serial B Port
The rear RJ45 Serial B Port is a fully function serial port that can support any standard serial device.
Using an RJ45 connector for a serial port allows direct support for serial port concentrators, which
typically use RJ45 connectors and are widely used in the high-density server market. For server applications
that use a serial concentrator to access the server management features of the baseboard, a standard
8-pin CAT-5 cable from the serial concentrator is plugged directly into the rear RJ45 serial port.
To allow support of either of two serial port configuration standards used by serial port concentrators, the
J5A2 jumper block located directly behind the rear RJ45 serial port must be jumpered appropriately
according to the desired standard.
NOTE: By default as configured in the factory, the R700 mainboard will have the rear RJ45 serial port
configured to support a DSR signal which is compatible with the Cisco* standard.
For serial concentrators that require a DCD signal, the J5A2 jumper block must be configured as follows:
The Serial Port jumper in position 1 and 2. Pin 1 on the jumper is denoted by an arrow directly next to the
jumper block. The following diagram provides the jumper block pin-out for this configuration.
BMC
Bus
Exchange
SIO
2 to 1
Mux
Level
shifter
Level
Shifter
Header
Rear
RJ45
Serial B
Serial A
DCD to Pin#7
PIN 1