USB SPI Protocol Adapter
Serial Peripheral Interface (SPI) is a handy solution to the synchronization problem that has to be overcome for devices to communicate. A USB SPI adapter allows a bidirectional communication between USB and SPI. Common devices that utilize SPI interface include but are not limited to sensors, shift registers, and SD cards.
SPIs use separate data and clock lines as well as an additional line used to select the device with which to communicate. The clock line helps to keep both ends in perfect synchronization. It is the clock that signals the slave when to sample bits in the data line. Power for the adaptor is supplied through the USB port. You will have to install drivers first to use an USB to SPI adapter.
Unlike most other protocols, SPIs are full duplex, meaning they have separate send and receive lines. It is therefore possible to send and receive data at the same time. Its other major benefit is the lack of lack of high-level protocol enabling high-speed communication.