use circular dma buffer for rx

5 files changed, 28 insertions, 24 deletions

diff --git a/stm32f091/consts.h b/stm32f091/consts.h
index 0a8acec..3d2ef5a 100644
--- a/stm32f091/consts.h
+++ b/stm32f091/consts.h
@@ -3,10 +3,10 @@
 #include "wifi.h"
 
 #define WS_SERVER_PORT "80"
-#define WS_SERVER_MAX_CHANNELS 2
+#define WS_SERVER_MAX_CHANNELS 4
 
 #define WS_DMA_RX_BUFFER_SIZE 100
-#define WS_DMA_TX_BUFFER_SIZE 100
+#define WS_DMA_TX_BUFFER_SIZE 1024
 
 #define WS_PINOUT_I2C_SDA_PIN GPIO_PIN_9
 #define WS_PINOUT_I2C_SDA_PORT GPIOB
diff --git a/stm32f091/esp8266.c b/stm32f091/esp8266.c
index db134a0..754b45b 100644
--- a/stm32f091/esp8266.c
+++ b/stm32f091/esp8266.c
@@ -17,6 +17,8 @@
 }
 
 uint8_t g_ws_esp8266_dma_rx_buffer[WS_DMA_RX_BUFFER_SIZE];
+unsigned int g_ws_esp8266_dma_rx_head = 0;
+unsigned int g_ws_esp8266_dma_rx_tail = 0;
 uint8_t g_ws_esp8266_dma_tx_buffer[WS_DMA_TX_BUFFER_SIZE];
 
 void DMA1_Ch1_IRQHandler(void) { HAL_DMA_IRQHandler(&hdma_usart1_rx); }
@@ -24,19 +26,30 @@ void DMA1_Ch2_3_DMA2_Ch1_2_IRQHandler(void) { HAL_DMA_IRQHandler(&hdma_usart1_tx
 void USART1_IRQHandler(void) {
 	if (__HAL_UART_GET_FLAG(&huart1, UART_FLAG_IDLE)) {
 		__HAL_UART_CLEAR_IDLEFLAG(&huart1);
-		HAL_UART_RxCpltCallback(&huart1);
-		HAL_UART_DMAStop(&huart1);
-		ws_esp8266_start_receive();
+		// https://stackoverflow.com/questions/71039052/hal-uartex-rxeventcallback-circular-dma-what-address-is-the-data
+		g_ws_esp8266_dma_rx_head = huart1.RxXferSize - huart1.hdmarx->Instance->CNDTR;
+
+		ws_esp8266_incoming_data_chunk();
 	}
 	HAL_UART_IRQHandler(&huart1);
 }
 
-void HAL_UART_RxCpltCallback(UART_HandleTypeDef* huart) {
-	size_t len = strlen((char*) g_ws_esp8266_dma_rx_buffer);
-	if (len > 0) ws_server_req_incoming(g_ws_esp8266_dma_rx_buffer, len);
-
-	memset(g_ws_esp8266_dma_rx_buffer, 0, WS_DMA_RX_BUFFER_SIZE);
-	ws_esp8266_start_receive();
+void ws_esp8266_incoming_data_chunk() {
+	if (g_ws_esp8266_dma_rx_head == g_ws_esp8266_dma_rx_tail) return; // no new data
+	if (g_ws_esp8266_dma_rx_head > g_ws_esp8266_dma_rx_tail) {
+		// read from tail until head
+		ws_server_req_incoming(&g_ws_esp8266_dma_rx_buffer[g_ws_esp8266_dma_rx_tail],
+			g_ws_esp8266_dma_rx_head - g_ws_esp8266_dma_rx_tail);
+	} else /* if (g_ws_esp8266_dma_rx_head < g_ws_esp8266_dma_rx_tail) */ {
+		// read from tail until end of buffer
+		ws_server_req_incoming(&g_ws_esp8266_dma_rx_buffer[g_ws_esp8266_dma_rx_tail],
+			WS_DMA_RX_BUFFER_SIZE - g_ws_esp8266_dma_rx_tail);
+		// read from buffer begin until head
+		ws_server_req_incoming(&g_ws_esp8266_dma_rx_buffer[0], // yes i know this looks dumb
+			g_ws_esp8266_dma_rx_head);
+	}
+	// finish read by shifting tail forward
+	g_ws_esp8266_dma_rx_tail = g_ws_esp8266_dma_rx_head;
 }
 
 void ws_esp8266_send(uint8_t* data, size_t size) {
@@ -54,11 +67,6 @@ void ws_esp8266_send(uint8_t* data, size_t size) {
 	__HAL_UART_ENABLE_IT(&huart1, UART_IT_TXE);
 }
 
-void ws_esp8266_start_receive() {
-	HAL_UART_Receive_DMA(&huart1, g_ws_esp8266_dma_rx_buffer, WS_DMA_RX_BUFFER_SIZE);
-	__HAL_DMA_DISABLE_IT(&hdma_usart1_rx, DMA_IT_HT);
-}
-
 void ws_esp8266_connect() {
 	ws_esp8266_send_seq("AT+CWJAP=\"" WS_ESP8266_WLAN_SSID "\",\"" WS_ESP8266_WLAN_PASSWD "\"\r\n");
 }
diff --git a/stm32f091/esp8266.h b/stm32f091/esp8266.h
index 66ccfba..94a7356 100644
--- a/stm32f091/esp8266.h
+++ b/stm32f091/esp8266.h
@@ -19,14 +19,11 @@ void DMA1_Ch1_IRQHandler(void);
 /** @brief USART1 interrupt handler */
 void USART1_IRQHandler(void);
 
-/** @brief receive chunk complete */
-void HAL_UART_RxCpltCallback(UART_HandleTypeDef* huart);
-
 /** @brief send data to esp over uart with dma */
 void ws_esp8266_send(uint8_t* data, size_t size);
 
-/** @brief start dma receive and reset half-transfer interrupt flag */
-void ws_esp8266_start_receive();
+/** @brief line idle, handle new data on dma buffer */
+void ws_esp8266_incoming_data_chunk();
 
 /** @brief connect to access point using wifi.h credentials */
 void ws_esp8266_connect();
diff --git a/stm32f091/server.c b/stm32f091/server.c
index d4f7e20..8001380 100644
--- a/stm32f091/server.c
+++ b/stm32f091/server.c
@@ -127,9 +127,8 @@ void ws_server_req_incoming(uint8_t* data, size_t size) {
 			}
 			case WS_SERVER_LM_CIPSEND_LISTENING: {
 				if (next_few_bytes_are("SEND OK")) {
-					i += 6;
-					// g_ws_server_parser.mode = WS_SERVER_LM_IDLE;
 					ws_server_req_respond_end(0);
+					// g_ws_server_parser.mode = WS_SERVER_LM_IDLE;
 				}
 				break;
 			}
diff --git a/stm32f091/setup.c b/stm32f091/setup.c
index 1971809..3bf331f 100644
--- a/stm32f091/setup.c
+++ b/stm32f091/setup.c
@@ -53,7 +53,7 @@ DMA_HandleTypeDef hdma_usart1_rx = {
 	.Init.MemInc = DMA_MINC_ENABLE,
 	.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE,
 	.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE,
-	.Init.Mode = DMA_NORMAL,
+	.Init.Mode = DMA_CIRCULAR,
 	.Init.Priority = DMA_PRIORITY_LOW,
 };