SWRU626 December 2025 CC3501E , CC3551E
The I2C provides an interface to the DMA controller with two separate channels. The DMA operation of the I2C is enabled through the I2C event and DMA peripheral registers. When the DMA functionality is enabled, the I2C asserts a DMA request on the selected channel when the associated FIFO can transfer data.
For the receive channel, a DMA transfer request is asserted whenever the amount of data in the receive FIFO is at or above the FIFO trigger level configured in the I2Cx.FIFOCTL register.
For the transmit channel, a request is asserted whenever the transmit FIFO contains fewer characters than the FIFO trigger level configured in the I2Cx.FIFOCTL register.
EVENT0 register are used to setup the trigger signaling for the DMA.This can be setup in a flexible way to trigger the DMA for Controller or Target and receive or transmit events. Software should avoid using the same trigger source for multiple EVENT lines concurrently.