The "CH376S USB read/write module" has a CH376S chip onboard which does most of the hard work for you. All you have to do is send the module some commands from the Arduino and the CH376S chip will do the rest. You can communicate with the module in three different ways: Parallel communication SPI communication and Serial (UART) communication.
CH376 is used as file manage control chip, used to MCU system read/write file in USB Flash Drive or SD card.
supports USB-Device Mode and USB-HOST Mode. Set the basic firmware of USB communication protocol in the inner.
It is also set firmware of special communication protocol to deal with Mass-Storage devices, communication interface firmware of SD card, FAT16, FAT32 and FAT12 file system manage firmware in the inner.
CH376 supports three communication interfaces: 8-bit parallel, SPI interface or asynchronism serial interface.
The USB-DEVICE Mode of CH376 is totally compatible with CH372, the USB-HOST Mode of CH375 is basically compatible with CH375.