TN0897

SPI communication flow

Doc ID 023176 Rev 2

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Figure 3.

Communication principle of the ST SPI

2.2

Command byte

Each communication frame starts with a command byte. It consists of an operating code

which specifies the type of operation (<Write>, <Read>, <Read and Clear>, <Read Device

Information>) and a 6 bit address. If less than 6 address bits are required, the remaining bits

are unused but are reserved.