#include "stm32f10x.h"
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

static xQueueHandle USART1_TxQueue;

uint8_t USART1_PutChar( uint8_t cOutChar )
{
uint8_t xReturn;

if( xQueueSend( USART1_TxQueue, &cOutChar, 10 ) == pdPASS )
{
xReturn = pdPASS;
USART_ITConfig( USART1, USART_IT_TXE, ENABLE );
}
else
{
xReturn = pdFAIL;
}

return xReturn;
}

void USART1_PutString( const uint8_t * pcString )
{
uint8_t *pxNext;

pxNext = ( uint8_t * ) pcString;
while( *pxNext )
{
USART1_PutChar( *pxNext );
pxNext++;
}
}

void HelloWorldTask(void *pvParameters)
{
for(;;)
{
USART1_PutString("Hello World!\n");
vTaskDelay( 1000 );
}
}

void USART1_IRQHandler( void )
{
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
uint8_t cChar;

if( USART_GetITStatus( USART1, USART_IT_TXE ) == SET )
{
if( xQueueReceiveFromISR( USART1_TxQueue, &cChar, &xHigherPriorityTaskWoken ) == pdTRUE )
{
USART_SendData( USART1, cChar );
}
else
{
USART_ITConfig( USART1, USART_IT_TXE, DISABLE );
}
}

portEND_SWITCHING_ISR( xHigherPriorityTaskWoken );
}

int main(void)
{
NVIC_InitTypeDef NVIC_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
USART_InitTypeDef USART_InitStructure;

/* Enable USART1 GPIO clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_GPIOA | RCC_APB2Periph_AFIO, ENABLE);

/* Enable UART1 clock */
RCC_APB2PeriphClockCmd(RCC_APB2Periph_USART1, ENABLE);

/* Enable the USART1 Interrupt */
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = configLIBRARY_LOWEST_INTERRUPT_PRIORITY;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);

/* Configure USART1 Tx as alternate function push-pull */
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

/* Configure USART1 Rx as input floating */
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
GPIO_Init(GPIOA, &GPIO_InitStructure);

/* Configure USART1 parameters 115200 8n1 noHW Tx+Rx*/
USART_InitStructure.USART_BaudRate = 115200;
USART_InitStructure.USART_WordLength = USART_WordLength_8b;
USART_InitStructure.USART_StopBits = USART_StopBits_1;
USART_InitStructure.USART_Parity = USART_Parity_No;
USART_InitStructure.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
USART_InitStructure.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
USART_Init(USART1, &USART_InitStructure);
USART_Cmd(USART1, ENABLE);

/* Create TxQueue for USART1 */
USART1_TxQueue = xQueueCreate( 256, ( unsigned portBASE_TYPE ) sizeof( uint8_t ) );

USART1_PutString("Program started!\n");
USART1_PutString("================\n");

xTaskCreate(HelloWorldTask, "HelWor", configMINIMAL_STACK_SIZE, NULL, 2, NULL);

vTaskStartScheduler();

for(;;)
{
}
}