The 6270A Pressure Controller's USB port on the back panel can be plugged into a computer and then the 6270A can be communicated with with RS232 communications (or files can be transferred to/from the 6270A like it's an external drive).
1. To use the USB connection for RS232 communications follow this menu path on the 6270A touch screen: Setup --> Instrument Setup --> Remote Port --> USB Setup
Ensure that "Remote IF" is set to Terminal and "RS232 Emulation" is set to ON.
Check the baud rate, etc. on the prior screen by clicking on RS-232 Setup.
On the prior screen, ensure that "Emulation Mode" is set to SCPI. Check the baud rate, etc. by clicking on RS-232 Setup.
With the above settings, when you plug the 6270A into a computer with a USB cable the computer should recognize that a new device is connected and try to load/find the driver for it. If it does not automatically do this, copy the below file named usbser.sys to this path, C:\Windows\System32\drivers and then have Windows search for it again. If Windows doesn't find it, manually direct Windows to this folder.
Then go to Windows Device Manager --> Ports (COM & LPT) and see if a new device is there with an assigned COM port. If it has a yellow alert, try to update the driver file.
2. To use the USB connection for file transfers (screen images saved by the 0 SAVE button, or firmware update files), follow this menu path on the 6270A touch screen: Setup --> Instrument Setup --> Remote Port --> USB Setup
Ensure that "Remote IF" is set to Computer and "RS232 Emulation" is set to OFF.
See this article for the necessary commands to minimally communicate with a 6270A controller by remote commands, 6270A Pressure Controller Setup in COMPASS for Pressure