newRPL devices can communicate with newRPL Desktop by connecting the calculator to the host with a USB cable. There's some additional steps needed on various operating systems in order to communicate with the calculator:

Windows No additional steps needed, just plug it.

Linux The current user (the user newRPL Desktop is running as) needs to have read/write permissions to USB devices. Create a new group usbdevices, then add the current user to that group. Next, create a file (as root) /etc/udev/rules.d/50-HIDDevices.rules, containing the following two lines:

KERNEL=="hidraw*", SUBSYSTEM=="hidraw", MODE="0664", GROUP="usbdevices"
SUBSYSTEM=="usb", ATTR{bInterfaceClass}=="03", MODE="0664", GROUP="usbdevices"

This will indicate the system to assign the group usbdevices to all new HID devices, and permits read/write to members of that group.

freeBSD The current user (the user newRPL Desktop is running as) needs to have read/write permissions to USB devices. Create a new group usbdevices, then add the current user to that group. Next, create a file (as root) /etc/devfs.rules, containing the following:

[localrules=5]
add path 'ugen*' mode 0660 group usbdevices
add path 'usb/*' mode 0660 group usbdevices
add path 'uhid*' mode 0660 group usbdevices

Finally, edit the file (as root) /etc/rc.conf and add a line at the end:

devfs_system_ruleset="localrules"