Drivers for the ASIX/MOSChip MCS7840 USB 2.0 to Quad Serial Controller can be downloaded below for x64 versions of Windows. This devices is a converter from USB 2.0 to (4) Serial RS232 ports.
ASIX/MOSChip MCS7840 Driver
File: MCS7840_7820_7810_Windows_64bit_Driver_v2.0.8.0_WHCK_Binary.zip
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