Diff: main.cpp

Revision:

0:1c6e43f7bfd5

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Fri Mar 06 11:06:18 2015 +0000
@@ -0,0 +1,72 @@
+/* mbed library for using USART DMA in STM32F401RE.
+ * Copyright (c) 2015 Match
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "mbed.h"
+
+uint8_t data[] = "Hello.\n"
+                 "How are you?\n"
+                 "abcdefghijklmnopqrstuvwxyz\n"
+                 "ABCDEFGHIJKLMNOPQRSTUVWXYZ\n"
+                 "See you.\n\n";
+
+DMA_HandleTypeDef usartTxDma;
+USART_HandleTypeDef usart;
+
+void Init();
+
+int main() {
+    Init();
+    
+    HAL_USART_Transmit_DMA(&usart, data, sizeof(data));
+    
+    while(1) {
+        
+    }
+}
+
+void Init() {
+    // DMA
+    // USART2 TX is DMA1 channel 4 stream 6. Look at table 28 in STM32F401 reference manual.
+    __DMA1_CLK_ENABLE();
+    usartTxDma.Instance = DMA1_Stream6;
+    usartTxDma.Init.Channel = DMA_CHANNEL_4;
+    usartTxDma.Init.Direction = DMA_MEMORY_TO_PERIPH;
+    usartTxDma.Init.PeriphInc = DMA_PINC_DISABLE;
+    usartTxDma.Init.MemInc = DMA_MINC_ENABLE;
+    usartTxDma.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;  // 8 bit
+    usartTxDma.Init.MemDataAlignment = DMA_PDATAALIGN_BYTE;     // 8 bit
+    usartTxDma.Init.Mode = DMA_NORMAL;
+    usartTxDma.Init.Priority = DMA_PRIORITY_VERY_HIGH;
+    usartTxDma.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
+    HAL_DMA_Init(&usartTxDma);
+    
+    // USART pin
+    __GPIOA_CLK_ENABLE();
+    GPIO_InitTypeDef usartTxd;
+    usartTxd.Pin = GPIO_PIN_2;
+    usartTxd.Mode = GPIO_MODE_AF_PP;
+    usartTxd.Pull = GPIO_NOPULL;
+    usartTxd.Speed = GPIO_SPEED_HIGH;
+    usartTxd.Alternate = GPIO_AF7_USART2;
+    HAL_GPIO_Init(GPIOA, &usartTxd);
+    
+    // USART
+    __USART2_CLK_ENABLE();
+    usart.Init.BaudRate = 921600;
+    usart.Init.WordLength = USART_WORDLENGTH_8B;
+    usart.Init.StopBits = USART_STOPBITS_1;
+    usart.Init.Parity = USART_PARITY_NONE;
+    usart.Init.Mode = USART_MODE_TX;    // transmit only mode
+    usart.Instance = USART2;
+    usart.hdmatx = &usartTxDma;
+    HAL_USART_Init(&usart);
+}