Serial NOR devices typically connect to a host MCU/MPU via an SPI or SPI-like bus. Eight-pin devices, with the functions listed in Table - NOR SPI BSP functions, or similar, are common, and are often employed with the HOLD and WP pins held high (logic low, or inactive), as shown in Table - NOR SPI BSP functions . As with any SPI device, four signals are used to communicate with the host (CS, SI, SCK and SO).
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