TMS320F28377D: DMA problems

here is a ADC setting, using timer0 int to trigger sample, the input pin can be measured with a voltage about 0.8~0.9V, but when reading the result using ADC_readResult(), the result is very low, about 0~30, what can be the problem?

Hello,

Are you seeing the timer0_cnt value increment in the ISR? For the DMA,what variable types are dma_src and dma_dest? And can you check the status of the DMA registers after the software trigger has been stepped over?

Best Regards,

Delaney

i used Version: 20.3.0.14 1.9.0 CCS to develop my board and added timer0_cnt to the watch screen, when system running, timer0_cnt incremented, but i found that source data had not been moved from dma_src to dma_dst,  as in the program i used two "const void pointer "src, dst" to set the source address and destination address, but it does not work. i used the syscfg tool to config the DMA, not a register configuration by myself.

i set the pointer "src" "dst" after the DMA initialization procedure, so it does not work...

Hello,

Apologies for my late reply. Can you make sure the structure of your variables matches the below exactly:

uint16_t dma_src_buffer[BUFFER_SIZE];

const void *dma_src = (const void *)dma_src_buffer;

You will need to use a const void pointer to the GSRAM buffer for the Sysconfig settings (rather than passing in the buffer itself).

Thanks,

Delaney

the SYSCFG initialization program just set the address before assignment, so i think the register cannot get the right address and it does not work, this might be the problem using SYSCFG.

Hello,

Can you take a look at the spi_ex5_loopback_dma example in C2000ware path: [C2000ware install]\driverlib\f2838x\examples\c28x\spi ? It shows the proper syntax for how to define arrays (sData and rData in this example) in the main file and use their addresses in DMA Sysconfig. Can you make sure your syntax is matching?

Best Regards,

Delaney