NUC972 UART RX DMA 问题

1万 · 2021-6-10 09:22

目的: 用DMA 把串口9的接收数据放到一个数组代码:
                     CHAR buf[]={0x03,0x03,0x9C,0x4B,0x00,0x01};

                     outpw(REG_GDMA_CTL0, 0x0);
                     outpw(REG_GDMA_SRCB0,REG_UART9_RBR);//source
                     outpw(REG_GDMA_DSTB0,(uint32_t)DMARecBuf);//destination
                     outpw(REG_GDMA_TCNT0,7);

                     outpw(REG_GDMA_CTL0,(1<<7)  | (1<<16));
                     outpw(REG_GDMA_CTL0,inpw(REG_GDMA_CTL0)|1);

                     comSend(buf,6);

                     while(!(inpw(REG_GDMA_INTCS) & 0x100));
                     outpw(REG_GDMA_INTCS,0x100);
问题点             bug = DMARecBuf[0]; //如果增加这一句代码后，就没有接收数据到DMARecBuf

只看该作者 · 2021-6-10 09:28

是楼主的 typo 吗？从上面看 GDMA使用的是 Channel 0, 最后却是 REG_GDMA_INTCS: 0x100 设置的是 Channel 1的中断？

只看该作者 · 2021-6-10 09:28

Publication Release Date: Dec. 15, 2015
- 321 - Revision V1.30
NUC970 TECHNICAL REFERENCE MANUAL
[8] TC0F
Channel 0 Terminal Count
0 = Channel does not expire.
1 = Channel expires; this bit is set only by GDMA hardware, and clear by software to
write logic 1.
TC0 is the GDMA interrupt flag. TC0 or GDMATERR0 will generate interrupt

1万 · 2021-6-11 11:58

这个系列越来越火了，看来我要研究研究。

只看该作者 · 2021-6-11 13:16

参考这个：
https://github.com/OpenNuvoton/NUC980_NonOS_BSP/tree/master/SampleCode/UART_PDMA