Most 721 series plotters do not have a "true" USB interface. Instead, they contain an internal USB-to-Serial chip. To make your PC recognise the device, you must install one of the following virtual COM port drivers: Common for high-quality serial conversions.
Often found in older or legacy 721 models.
Run the installer before plugging in the plotter. rohs cutting plotter 721 drivers windows 10
The RoHS 721 typically uses or DMPL command languages. Popular software choices include: Software for JinKa JK-721 plotter - PlotCalc
You can typically download these from Driver Scape or official support portals like USCutter . Most 721 series plotters do not have a "true" USB interface
Plug the USB cable into a rear port of your PC (rear ports provide more stable power) and turn the plotter on. Verify in Device Manager: Right-click the Start button and select Device Manager .
Right-click the device > > Port Settings > Advanced . Often found in older or legacy 721 models
Look under . Your plotter should appear as "USB-Serial CH340" or similar, assigned to a port like COM3 . Configure the Port:
Frequently used in Chinese-manufactured hardware.
Ensure the is set between 1 and 4 . Numbers higher than 10 often cause communication errors in cutting software. Compatible Software for the 721 Plotter