Serial communication is the most stable communication method. If your computer does not have a serial input, you can by-pass this through a serial to USB adapter.
We recommend all Serial to USB-adapters with FTDI-chip. They can be found on Google, eBay or Amazon if you search for "FTDI serial to USB-adapter". Don't forget to install the USB-driver for the adapter which is needed for the computer to recognize it.
Here are drivers for the most common USB-adapters.
FTDI-adapter
Keyspan/Triplite USA19HS
Prolific-adapter
See these image below for how to connect your serial cable and USB-adapter depending on what kind of adapter you have.
Serial to USB adapter
Connect the serial cable in the cutter and then adapter between the serial cable and computer.
Adapter with USB-extension
Even though this cable is long and would be enough between the cutter and computer the serial cable still need to be connected as it converts the signal from the cutting plotter so that the cutter can read it.
Incorrect way of connecting the adapter
If you connect the adapter between the cutter and serial cable the communication will not work.