TMS570LS3137 MCU Experts,
Sorry, I am using this old thread because I do not find how to start a new thread.
My questions are about TMS570LS3137 DMA application. It's urgent for us, hope to get your quick reply.
1. Background:
I have Dual high speed ADC chip with SPI port. Its dual SPI outputs are connected to MCU MibSPI-1 and MibSPI-3.
SPI-1 is in Master Mode and SPI-3 in Slave Mode. SPI-1 generates the SPI_/CS and SPI_CLK to drive the ADC SPI port and SPI-3 port simultaneously.
In order to minimize the CPU operation latency, I used SPI multi-buffer (using external trigger) and DMA to read data so that the entire process is handled by "hardware".
2. My question
SPI-1 multi-buffer TG-0 was defined to have only Buffer-0. i.e. every external trigger, SPI-1 will transmit ONE dummy data, and receive ONE data to Buffer-0 RX. SPI-3 also uses its TG0 with Buffer-0 only. SPI-3 will receive ONE data to Buffer-0 RX at same time.
Both SPI-1 and SPI-3 multi-buffer work well (can see data received in TG0 RX). Then I assigned DMA channel-0 and channel-1 for SPI-1 TG0 RX and SPI-3 TG0 RX respectively. The settings are pretty similar for both channels.
I can see SPI-3 has transferred the data from TG0 RX to the destination in RAM. However, the DMA channel for SPI-1 did not work.
Why? any comments are welcome.
(I tried using different DMA channels, even swapped the channels of SPI-1 and SPI-3, it's the same results - the DMA for SPI-3 TG0 RX worked, but not work for SPI-1)
