1988052_en-US

[#1]

MCXN947 DAC14 DMA not working

Hi,

I am working with the FRDM-MCXN947 development board, MCUXpresso IDE v24.9 and SDK2.16.100 FRDM-MCXN947.

The DAC is supposed to output data from an array with the help of the DMA controller (find attached code).

The interrupt for the DAC is executed regularly. The FIFO status seems correct, the EMPTY and LESS_THAN_LEVEL bits are set.

The problem is probably with the DMA controller. There may also be a command missing here.

Unfortunately I couldn't find an example - hence my call for help to the community.

Thanks,

Klaus

Analog(ADC|CMP|DAC|OpAmps)MCXNRe: MCXN947 DAC14 DMA not working

Hi @klausfetscher,

After the corresponding DMA enable register fields becomes 1, the error flags can only generate an interrupt.

The Period Trigger Mode Conversion Complete Flag (PTGCOCO) is a warning flag. The error flags are FIFO Overflow Flag (OF) and FIFO Underflow Flag (UF)

See section 43.3.6 DMA from MCX Nx4x Reference Manual

In order to know if the transmission has ended you can read the status flags from the DAC and use a mask to know only the value of the PTGCOCO.

Hope it helps you!

Re: MCXN947 DAC14 DMA not working

I found and corrected some errors. The transfer of the DAC data with the DMA and the output via the DAC now works.

At the end of a transmission I want to receive the kDAC14_PeriodTriggerCompleteInterruptEnable. Unfortunately this interrupt is not triggered.

Any idea ?

Klaus