38.6.3.1 Host - Client Operation

The Host - Client operation is available only on devices with two ADC instances. The ADC1 will be enabled as a Client of ADC0 instance when writing a one to the Client Enable bit in Control A register of the ADC1 instance (ADC1.CTRLA.ClientEN). When enabled, GCLK_ADC0 clock and ADC0 controls are internally routed to the ADC1 instance.

Figure 38-8. ADC Host - Client Block Diagram

In this mode of operation, the Client ADC is enabled by accessing the CTRLA register of Host ADC. In the same way, the Host ADC event inputs will be automatically routed to the Client ADC, meaning that the input events configuration must be done in the Host ADC (ADC0.EVCTRL).

ADC measurements can be started simultaneously on both ADC’s or interleaved. The trigger mode selection is available in the Host ADC Control C register (ADC0.CTRLC.DUALSEL).

To restart an interleaved sequence, the user can apply different options:
  • Flush the Host ADC (ADC0.SWTRIG.FLUSH = 1)
  • Disable/re-enable the Host ADC (ADC0.CTRLA.ENABLE)
  • Reset and reconfigure Host ADC (ADC0.CTRLA.SWRST = 1)
Figure 38-9. Interleaved Dual-Mode Trigger Selection