SPRUJ53B April 2024 – September 2024 TMS320F28P550SJ , TMS320F28P559SJ-Q1
In this mode, Channel 1 has high priority over all the other channels. Channels 2 to 6 have equal priority and each enabled channel is serviced in a round-robin fashion.
Higher priority: | CH1 |
Lower priority: | CH2 → CH3 → CH4 → CH5 → CH6 → CH2 → … |
Given an example where CH1, CH4, and CH5 are enabled in Channel 1 high-priority mode and CH4 is currently being processed. Then CH1 and CH5 both receive an interrupt trigger from the respective peripherals before CH4 completes. CH1 and CH5 are now both pending. When the current CH4 word transfer is completed, regardless of whether the DMA has completed the entire CH4 burst, CH4 execution is suspended and CH1 is serviced. After the CH1 burst completes, CH4 resumes execution.
Upon completion of CH4, CH5 is serviced. After CH5 completes, if there are no more channels pending, the round-robin state machine enters an idle state.
Typically Channel 1 is used in this mode for the ADC, since the data rate is so high. However, Channel 1 high-priority mode can be used in conjunction with any peripheral.