Add working dma example

examples/stm32/bsp/blackpill/blackpill.c

@@ -194,6 +194,11 @@ static void MX_USART1_UART_Init(void)
     Error_Handler();
   }
 
+  // Enable USART1 interrupt
+  // It must higher or equal than 5
+  HAL_NVIC_SetPriority(USART1_IRQn, 5, 0);
+  HAL_NVIC_EnableIRQ(USART1_IRQn);
+  
   // USART1 Pin configuration: TX (PA9), RX (PA10)
   GPIO_InitTypeDef GPIO_InitStruct = {0};
 
@@ -207,6 +212,8 @@ static void MX_USART1_UART_Init(void)
   GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_VERY_HIGH;
   GPIO_InitStruct.Alternate = GPIO_AF7_USART1;
   HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
+
+
 }
 
 static void MX_SPI1_Init(void)
@@ -321,12 +328,15 @@ static void MX_DMA_Init(void)
   hdma_usart1_rx.Init.Mode = DMA_NORMAL;
   hdma_usart1_rx.Init.Priority = DMA_PRIORITY_HIGH;
   hdma_usart1_rx.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
+
   if (HAL_DMA_Init(&hdma_usart1_rx) != HAL_OK)
   {
     // Initialization error handling
     Error_Handler();
   }
 
+  __HAL_LINKDMA(&huart1, hdmarx, hdma_usart1_rx);
+
     // DMA2_Stream3 (SPI1_TX) Interrupt Configuration
   HAL_NVIC_SetPriority(DMA2_Stream3_IRQn, 0, 0);
   HAL_NVIC_EnableIRQ(DMA2_Stream3_IRQn);
@@ -369,3 +379,8 @@ void DMA2_Stream2_IRQHandler(void)
 {
     HAL_DMA_IRQHandler(&hdma_usart1_rx);
 }
+
+void USART1_IRQHandler(void)
+{
+    HAL_UART_IRQHandler(&huart1);
+}

examples/stm32/nmbs/port.c

@@ -9,6 +9,13 @@ static int32_t write_socket(const uint8_t* buf, uint16_t count, int32_t byte_tim
 #ifdef NMBS_RTU
 static int32_t read_serial(uint8_t* buf, uint16_t count, int32_t byte_timeout_ms, void* arg);
 static int32_t write_serial(const uint8_t* buf, uint16_t count, int32_t byte_timeout_ms, void* arg);
+
+#if MB_UART_DMA 
+#include "queue.h"
+xQueueHandle rtu_rx_q;
+uint8_t      rtu_rx_b[MB_RX_BUF_SIZE];
+#endif
+
 #endif
 
 static nmbs_server_t* server;
@@ -47,6 +54,11 @@ nmbs_error nmbs_server_init(nmbs_t* nmbs, nmbs_server_t* _server)
     cb.write_single_register     = server_write_single_register;
     cb.write_multiple_registers  = server_write_multiple_registers;
 
+#if MB_UART_DMA 
+    rtu_rx_q = xQueueCreate(MB_RX_BUF_SIZE, sizeof(uint8_t));
+    HAL_UARTEx_ReceiveToIdle_DMA(&MB_UART, rtu_rx_b, MB_RX_BUF_SIZE);
+#endif
+
     nmbs_error status = nmbs_server_create(nmbs, server->id, &conf, &cb);
     if(status != NMBS_ERROR_NONE)
     {
@@ -202,6 +214,21 @@ int32_t write_socket(const uint8_t *buf, uint16_t count, int32_t byte_timeout_ms
 #ifdef NMBS_RTU
 static int32_t read_serial(uint8_t* buf, uint16_t count, int32_t byte_timeout_ms, void* arg)
 {
+#if MB_UART_DMA
+    uint32_t tick_start = HAL_GetTick();
+    while(uxQueueMessagesWaiting(rtu_rx_q) < count)
+    {
+        if(HAL_GetTick() - tick_start >= (uint32_t)byte_timeout_ms)
+        {
+            return 0;
+        }
+    }
+    for(int i = 0; i < count; i++)
+    {
+        xQueueReceive(rtu_rx_q, buf + i, 1);
+    }
+    return count;
+#else
     HAL_StatusTypeDef status = HAL_UART_Receive(&MB_UART, buf, count, byte_timeout_ms);
     if(status == HAL_OK)
     {
@@ -211,9 +238,13 @@ static int32_t read_serial(uint8_t* buf, uint16_t count, int32_t byte_timeout_ms
     {
         return 0;
     }
+#endif
 }
 static int32_t write_serial(const uint8_t* buf, uint16_t count, int32_t byte_timeout_ms, void* arg)
 {
+#if MB_UART_DMA 
+    HAL_UART_Transmit_DMA(&MB_UART, buf, count);
+#else
     HAL_StatusTypeDef status = HAL_UART_Transmit(&MB_UART, buf, count, byte_timeout_ms);
     if(status == HAL_OK)
     {
@@ -223,5 +254,25 @@ static int32_t write_serial(const uint8_t* buf, uint16_t count, int32_t byte_tim
     {
         return 0;
     }
+#endif
 }
+
+
+#if MB_UART_DMA
+void HAL_UARTEx_RxEventCallback(UART_HandleTypeDef *huart, uint16_t Size)
+{
+    BaseType_t xHigherPriorityTaskWoken = pdFALSE;
+    if(huart == &MB_UART)
+    {
+        for(int i = 0; i < Size; i++)
+        {
+            xQueueSendFromISR(rtu_rx_q, rtu_rx_b + i, &xHigherPriorityTaskWoken);
+        }
+        HAL_UARTEx_ReceiveToIdle_DMA(huart, rtu_rx_b, MB_RX_BUF_SIZE);    
+        portYIELD_FROM_ISR(xHigherPriorityTaskWoken);
+    }
+    // You may add your additional uart handler below
+}
+#endif
+
 #endif

examples/stm32/nmbs/port.h

@@ -21,8 +21,9 @@ extern "C" {
 
 #ifdef NMBS_RTU
 // modbus rtu
-#define MB_UART huart1
-#define RX_BUF_SIZE 256
+#define MB_UART         huart1
+#define MB_UART_DMA     1
+#define MB_RX_BUF_SIZE  256
 extern UART_HandleTypeDef MB_UART;
 #endif
 

examples/stm32/readme.md

@@ -6,15 +6,19 @@
 
 - Blackpill board
 - STM32F401CCUx 
-- USART1 with DMA
+- USART1 (with/without) DMA
   - PA9 : TX1
   - PA10 : RX1
+- SPI1 with DMA (connected to W5500)
+  - PB3 : SCK1
+  - PB4 : MISO1
+  - PB5 : MOSI1
+  - PA15 : NSS (Software select)
 
 ## Toolchain and environment
 
-Tested on Mac OS Sonoma(Apple Silicon M1) but other os having same toolchain should have no problem.
+Tested on Mac OS Sonoma(Apple Silicon) & Windows 10 but other os having same toolchain should have no problem.
 
-- STM32CubeMX 6.11.1
 - arm-none-eabi-gcc 
 - cmake
 - ninja
@@ -23,8 +27,3 @@ Tested on Mac OS Sonoma(Apple Silicon M1) but other os having same toolchain sho
   - CMake
   - cortex-debug
 
-## How to run
-
-1. Generate driver code from stm32f401ccux.ioc using STM32CubeMX
-2. Configure with CMake
-3. Launch with elf file or flash it