SPRUJ28E November 2021 – September 2024 AM68 , AM68A , TDA4AL-Q1 , TDA4VE-Q1 , TDA4VL-Q1
The FSM sequencer supports up to 16 steps that can be configured to perform analog-to-digital conversions. Each of the 16 steps can individually be enabled and configured to operate as software enabled steps or hardware enabled steps. Each step has its own programmable step configuration (ADC_CONFIG_j) and step delay (ADC_DELAY_j) registers that allow users to configure the ADC operation on a per-step basis.
The FSM sequencer enters Idle immediately after the ADC is enabled and remains in Idle while waiting for any of the 16 programmable steps to be enabled. When one or more step is enabled, the FSM sequencer will begin executing or skipping each step starting with the lowest and incrementing up through each step until the highest step has been executed or skipped. The FSM sequencer will execute enabled steps and skip disabled steps. Once all of the steps have been executed or skipped, the FSM sequencer will return to Idle or immediately begin repeating steps configured for continuous mode.
An ENDOFEQUENCE interrupt can be generated after the last enabled step has been executed. If any software enabled steps are configured for continuous operation and they are still enabled when the FSM sequencer has incremented through all the steps, the FSM sequencer will start the sequence again with the first enabled step. Hardware enabled steps are mapped to a hardware event and will need the hardware event to occur before being scheduled.
Figure 12-2 illustrates how the FSM sequencer works. Each shaded box represents a FSM state.
Figure 12-2 does not represent the number of SMPL_CLK cycles required by each state since some states implement user programmable delays that may require more than one SMPL_CLK cycle to complete.