Posted on May 17, 2011 at 09:31Hi,
I modified the SPP DMA example in order to
work with the UART
Everything is ok when I send strings from SRAM :p ,
the string stored in FLASH is not sent :-? .
Follow a piece of code with the uart inits
Any suggestion?
Stefano
------- Attach ------
void Uart0_Init()
{
DMA_InitTypeDef DMA_InitStruct;
/* UART0 configuration -------------------------------------------------------*/
/* UART0 configured as follow:
- Word Length = 8 Bits
- One Stop Bit
- No parity
- BaudRate = 115200 baud
- Hardware flow control enabled (RTS and CTS signals)
- Receive and transmit enabled
- Receive and transmit FIFOs are enabled
- Transmit and Receive FIFOs levels have 8 bytes depth
*/
UART_InitStructure.UART_WordLength = UART_WordLength_8D;
UART_InitStructure.UART_StopBits = UART_StopBits_1;
UART_InitStructure.UART_Parity = UART_Parity_No ;
UART_InitStructure.UART_BaudRate = 115200;
UART_InitStructure.UART_HardwareFlowControl = UART_HardwareFlowControl_None;
UART_InitStructure.UART_Mode = UART_Mode_Tx_Rx;
UART_InitStructure.UART_FIFO = UART_FIFO_Enable;
UART_InitStructure.UART_TxFIFOLevel = UART_FIFOLevel_1_2; /* FIFO size 16 bytes, FIFO level 8 bytes */
UART_InitStructure.UART_RxFIFOLevel = UART_FIFOLevel_1_2; /* FIFO size 16 bytes, FIFO level 8 bytes */
UART_DeInit(UART0);
UART_Init(UART0, &UART_InitStructure);
/* Enable the UART Receive interrupt: this interrupt is generated when the UART0 receive FIFO hold two data */
UART_ITConfig(UART0, UART_IT_Receive, ENABLE);
UART_DMACmd(UART0, UART_DMAReq_Tx, ENABLE);
/***************************DMA configuration**********************************/
DMA_SyncConfig(DMA_UART0_TX_Mask, ENABLE);
DMA_StructInit(&DMA_InitStruct);
DMA_InitStruct.DMA_Channel_LLstItm=0;
DMA_InitStruct.DMA_Channel_SrcAdd=(u32)(TxBuffer);
DMA_InitStruct.DMA_Channel_DesAdd=(u32)((&UART0->DR));
DMA_InitStruct.DMA_Channel_SrcWidth= DMA_SrcWidth_Byte;
DMA_InitStruct.DMA_Channel_DesWidth= DMA_DesWidth_Byte;
DMA_InitStruct.DMA_Channel_FlowCntrl= DMA_FlowCntrl1_DMA ;
DMA_InitStruct.DMA_Channel_Des = DMA_DES_UART0_TX;
DMA_InitStruct.DMA_Channel_TrsfSize = TXBUFFERSIZE;
DMA_ChannelSRCIncConfig (DMA_Channel1, ENABLE);
DMA_Init(DMA_Channel1,&DMA_InitStruct);
// DMA_ChannelCmd (DMA_Channel0,ENABLE);
/* Configure and enable the interrupt controller */
/*Enable VIC clock*/
VIC_Config(UART0_ITLine, VIC_IRQ, 1);
VIC_ITCmd(UART0_ITLine, ENABLE);
UART_Cmd(UART0, ENABLE);
}
void Uart0_Write(char *string, u32 size)
{
// wait the end of previous tx
while(UART_GetFlagStatus(UART0, UART_FLAG_TxFIFOEmpty)==RESET);
UART_ITConfig(UART0, UART_IT_Transmit, DISABLE);
DMA_ChannelCmd (DMA_Channel1,DISABLE);//Enable the DMA channel
DMA_Channel1->SRC = (u32)string;
DMA_Channel1->CC &= 0xFFFFF000;
DMA_Channel1->CC |= size & 0x0FFF;
DMA_ChannelCmd (DMA_Channel1,ENABLE);//Enable the DMA channel
}
....
in the main the loop...
while(1)
{
char a[]={'a', 'b', '\r', '\n'};
Uart0_Write(a,4);
Uart0_Write(''Hello Dad I love you\r\n'', 22);
}
------- end Attach --
