9.5.1.2 Serial Register Readout
The device includes a mode where the contents of the internal registers can be read back on the SDOUT pin. This mode is useful as a diagnostic check to verify the serial interface communication between the external controller and the ADC.
By default, after power up and device reset, the SDOUT pin is in the high-impedance state. When the readout mode is enabled using the register bit <READOUT>, SDOUT outputs the contents of the selected register serially, described as follows.
- Set register bit <READOUT> = 1 to put the device in serial readout mode. This setting disables any further writes into the internal registers, EXCEPT the register at address 1.
- Note that the <READOUT> bit itself is also located in register 1.
The device can exit readout mode by writing <READOUT> to 0.
Only the contents of register at address 1 cannot be read in the register readout mode.
- Initiate a serial interface cycle specifying the address of the register (A7–A0) whose content is to be read.
- The device serially outputs the contents (D15–D0) of the selected register on the SDOUT pin.
- The external controller can latch the contents at the rising edge of SCLK.
- To exit the serial readout mode, reset register bit <READOUT> = 0, which enables writes into all registers of the device. At this point, the SDOUT pin enters the high-impedance state.