9.1.1 Interfacing to Microcontroller

Figure 76 displays a typical serial interface that may be observed when connecting the DACx0508 SPI serial interface to a (master) microcontroller type platform. The setup for the interface is as follows: The microcontroller output SPI CLK drives the SCLK pin of the DACx0508, while the DACx0508 SDI pin is driven by the MOSI pin of the microcontroller. The CS pin of the DACx0508 can be asserted from a general program input/output pin of the microcontroller. When data are to be transmitted to the DACx0508, the CS pin is taken low. The data from the microcontroller is then transmitted to the DACx0508, totaling 24 bits latched into the DACx0508 device through the falling edge of SCLK. CS is then brought high after the completed write. The DACx0508 requires data with the MSB as the first bit received.

Figure 76. Typical Serial Interface