47.7.6.1 MCP3910 Protocol Overview

In Two-Pin mode, the MCSPI interfaces to analog front-end ADC devices such as MCP3910. The MCP3910 device data output (SDO) is the host for the MOSI line, although the MCSPI generates the SPCK clock. MCSPI_CSRx.SCBR defines the frequency of the SPCK output clock. The MISO line is not used.

In Two-Pin mode, only two lines are used for communication, SPCK and MOSI.

In Two-Pin mode, MCSPI_CSR0.CPOL and MCSPI_CSR0.NCPHA must be set to '0'.

Figure 47-14. MCP3910 Basic Connection to MCSPI

Figure 47-15. Two-Pin MCP3910 Frame

SPI Two-Pin mode connects with up to four two-pin devices. Each MCP3910 product sends four times the same frame. See the following figure.

Figure 47-16. MCP3910 Communication Protocol