The device feature a serial peripheral interface and software protocol allowing operation on a simple 3-wire bus. The three bus signals are a clock input (SCLK), a serial data input (SI), and a serial data output (SO). Serial access to the device is enabled by CS# input. When it is in Dual Output read mode, the SI and SO pins become SIO0 and SIO1 pins for data output. The device provides sequential read operation on whole chip.