I am trying to embed a SBC inside a device. Power, weight and space are very limited. The two devices need to communicate with each other via Ethernet using a crossover cable. I would like to solder wires directly from the PCBs of both devices to a single Ethernet port. By using two pairs from each device I would be able to either interface them separately by splitting the 4 pairs again before connecting to a router or allow them to communicate via a crossover cable feeding back into the same port. This would allow me to remove an Ethernet port from one of the devices and save space.
For the crossover cable:
|----ETHERNET PORT-----| Device 1 -> CableSideA -> CableSideB -> Device 2 1 1 7 3 2 2 8 6 3 3 4 1 6 6 5 2
Here is a diagram I quickly made that might help explain:
- The crossover cable can be seen at the top left. This is an RJ45 connector (MALE) with wires crimped as seen in the diagram
- Below the crossover cable is the RJ45 (FEMALE) Port that both pcbs are wired to
- At the bottom there are both PCB pinouts
- The right diagram shows the cable that will be built to split the connection if I need to interface either one or both of the devices.
- The cable has on one end an RJ45 connector(MALE) that is split on the other end into two RJ45 connectors (MALE)
Is it possible to wire directly from the PCB's of device 1&2 to a single RJ45 port (HR911105A) using two pairs from each device (100BASE-T only utilizes two pairs) and then split this connection outside of the port?
Data Sheet of the port in question: HR911105A