LoopA BLM splitter cable schematic
… in case you need it, just wire up as shown in the diagram below, just follow the green wires - also note that pin2 on the DIN8 needs to be connected to pin2 on the MIDI-OUT jack. You will need 5 wires going out from the DIN8 jack into two DIN5 jacks.
Neat trick: the DIN8 connector only uses 5 pins, so you could potentially reuse an old MIDI cable for it and cut it in half (only if it has all 5 wires attached).