Epson MR Series Technical Reference Manual page 97

MR Series Technical Reference Manual
9. The Select Controller dialog box is displayed. Select the [Gunze,AHL,Serial]. Click Next.
10. The Port dialog box is displayed. Specify the Serial Port. Check the Auto Detect box or enter
the number of the COM port that you use. Click Next. Advanced is usually not needed.
CAUTION:
Be sure not to set the port to COM3/COM4.
Rev. I OS and Drivers 4-47