Get & Setup Debian-Ubuntu Brother FAX-1840C FAX Drivers
The Guide Include Links to Download and Install the Brother Printer FAX-1840C FAX Drivers for Linux-Mint/Lubuntu/Kubuntu/Xubuntu/Elementary-OS/Kali and others Ubuntu/Debian GNU/Linux Based OSs.
Brother furnish two different Drivers format for Linux: LPR & CUPS. The Brother CUPSwrapper driver is built on top of the LPR driver.
To Finalize the Brother Printer/Fax Installation for Linux Debian/Ubuntu Linux like You will Need to Install Both the LPR and CUPS Drivers.