... to extend serial transmission distance up to 2 km (multi-mode fiber) or up to 20 km (single- mode fiber). Note ... Fiber signal IN, OUT Working format Asynchronism, point to point or multi-point Direction control Adopt automatic send data control , auto distinguish ... 0-500Kbps, auto-sense signal serial baud rate Fiber wavelength Multi-mode 850nm, signal-mode 1310nm Electricity port transmission RS-232 ...