This pin is high impedance until the SPI output is enabled via nCS. Once the SPI is enabled by a low on nCS, the SDO is immediately driven high or low showing the global interrupt register 8'h50, bit 7. The Global Interrupt register, INT_GLOBAL, is the first byte to be shifted out. The SDO pin provides data out from the device to the processor. For a write command this is the only data that will be provided on the SDO pin. For a read command the one to three bytes of data from successive address will be provided on the SDO line. Figure 10-38 and Figure 10-39 shows examples of a single address read and of a three sequential address read utilizing the 32-bit burst read. The 32-bit burst read shows the global interrupt register followed by the three requested data bytes.
Example on how to read three bytes of data from one SPI read command.
If a read happens faster than 2 µs after a write the global fault flag status may not reflect any status change that the write may have initiated.