1 files changed, 150 insertions, 0 deletions
diff --git a/FreeRTOS/Demo/AVR_Dx_Atmel_Studio/RTOSDemo/serial/serial.c b/FreeRTOS/Demo/AVR_Dx_Atmel_Studio/RTOSDemo/serial/serial.c
new file mode 100644
index 000000000..59ccbbec5
--- /dev/null
+++ b/FreeRTOS/Demo/AVR_Dx_Atmel_Studio/RTOSDemo/serial/serial.c
@@ -0,0 +1,150 @@
+/*
+ * FreeRTOS Kernel V10.3.1
+ * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to
+ * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+ * the Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * 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.
+ *
+ * http://www.FreeRTOS.org
+ * http://aws.amazon.com/freertos
+ *
+ * 1 tab == 4 spaces!
+ */
+
+
+/* BASIC INTERRUPT DRIVEN SERIAL PORT DRIVER FOR IAR AVR PORT. */
+
+#include <stdlib.h>
+#include "FreeRTOS.h"
+#include "queue.h"
+#include "task.h"
+#include "serial.h"
+#include <avr/interrupt.h>
+
+#define USART_BAUD_RATE(BAUD_RATE) ((float)(configCPU_CLOCK_HZ * 64 / (16 * (float)BAUD_RATE)) + 0.5)
+ 
+static QueueHandle_t xRxedChars;
+static QueueHandle_t xCharsForTx;
+
+#define vInterruptOn() USART1.CTRLA |= (1 << USART_DREIE_bp)
+
+#define vInterruptOff() USART1.CTRLA &= ~(1 << USART_DREIE_bp)
+
+xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength )
+{
+    portENTER_CRITICAL();
+    {
+        /* Create the queues used by the com test task. */
+        xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) );
+        xCharsForTx = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) );
+
+        USART1.BAUD = (uint16_t)USART_BAUD_RATE(ulWantedBaud); /* set baud rate register */
+
+        USART1.CTRLA = 1 << USART_LBME_bp       /* Loop-back Mode Enable: enabled */
+                     | USART_RS485_OFF_gc       /* RS485 Mode disabled */
+                     | 1 << USART_RXCIE_bp;     /* Receive Complete Interrupt Enable: enabled */
+
+        USART1.CTRLB = 1 << USART_RXEN_bp       /* Reciever enable: enabled */
+                     | USART_RXMODE_NORMAL_gc   /* Normal mode */
+                     | 1 << USART_TXEN_bp;      /* Transmitter Enable: enabled */
+    }
+    
+    portEXIT_CRITICAL();
+    
+    /* Unlike other ports, this serial code does not allow for more than one
+    com port.  We therefore don't return a pointer to a port structure and can
+    instead just return NULL. */
+    return NULL;
+}
+/*-----------------------------------------------------------*/
+
+signed portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, TickType_t xBlockTime )
+{
+    /* Get the next character from the buffer.  Return false if no characters
+    are available, or arrive before xBlockTime expires. */
+    if( xQueueReceive( xRxedChars, pcRxedChar, xBlockTime ) )
+    {
+        return pdTRUE;
+    }
+    else
+    {
+        return pdFALSE;
+    }
+}
+/*-----------------------------------------------------------*/
+
+signed portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed char cOutChar, TickType_t xBlockTime )
+{
+    /* Return false if after the block time there is no room on the Tx queue. */
+    if( xQueueSend( xCharsForTx, &cOutChar, xBlockTime ) != pdPASS )
+    {
+        return pdFAIL;
+    }
+    
+    vInterruptOn();
+    
+    return pdPASS;
+}
+/*-----------------------------------------------------------*/
+
+void vSerialClose( xComPortHandle xPort )
+{
+    /* Turn off the interrupts.  We may also want to delete the queues and/or
+    re-install the original ISR. */
+
+    portENTER_CRITICAL();
+    {
+        vInterruptOff();
+        USART1.CTRLB &= (1 << USART_RXEN_bp);
+    }
+    portEXIT_CRITICAL();
+}
+/*-----------------------------------------------------------*/
+
+ISR(USART1_RXC_vect)
+{
+signed char ucChar, xHigherPriorityTaskWoken = pdFALSE;
+
+    /* Get the character and post it on the queue of Rxed characters.
+    If the post causes a task to wake force a context switch as the woken task
+    may have a higher priority than the task we have interrupted. */
+    ucChar = USART1.RXDATAL;
+
+    xQueueSendFromISR( xRxedChars, &ucChar, &xHigherPriorityTaskWoken );
+
+    if( xHigherPriorityTaskWoken != pdFALSE )
+    {
+        portYIELD_FROM_ISR();
+    }
+        
+}
+
+ISR(USART1_DRE_vect)
+{
+signed char cChar, cTaskWoken = pdFALSE;
+
+    if( xQueueReceiveFromISR( xCharsForTx, &cChar, &cTaskWoken ) == pdTRUE )
+    {
+        /* Send the next character queued for Tx. */
+        USART1.TXDATAL = cChar;
+    }
+    else
+    {
+        /* Queue empty, nothing to send. */
+        vInterruptOff();
+    }
+}