JAJSOX0A March 2024 – June 2024 ADS127L18
ADVANCE INFORMATION
The SPI programming mode is selected by connecting the MODE pin to IOVDD. In SPI mode, the hardware programming mode is disabled and the device is programmed through the SPI registers. Figure 7-43 illustrates the SPI pins.
The SPI serial interface consists of four signals: CS, SCLK, SDI, and SDO (hardware programming functions are subsequently removed from the pin names). The interface operates in the passive mode where SCLK is an input to the device, driven by the host. The interface is compatible to SPI mode 1 (CPOL = 0 and CPHA = 1). In SPI mode 1, SCLK idles low, and data are updated on SCLK rising edges and read on SCLK falling edges. The interface supports full-duplex operation, meaning input data and output data are transmitted simultaneously.
An 8-bit CRC validates error-free data transmission between the host and ADC. A 16-bit CRC register value detects register map changes after the initial register data are loaded.