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/*
* FreeRTOS Kernel V10.2.1
* Copyright (C) 2019 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 UART0.
*/
/* Library includes. */
#include "75x_uart.h"
#include "75x_gpio.h"
#include "75x_eic.h"
#include "75x_mrcc.h"
/* Scheduler includes. */
#include "FreeRTOS.h"
#include "queue.h"
/* Demo application includes. */
#include "serial.h"
#define serINVALID_QUEUE ( ( QueueHandle_t ) 0 )
#define serNO_BLOCK ( ( TickType_t ) 0 )
/*-----------------------------------------------------------*/
/* Queues used to hold received characters, and characters waiting to be
transmitted. */
static QueueHandle_t xRxedChars;
static QueueHandle_t xCharsForTx;
static volatile portBASE_TYPE xQueueEmpty = pdTRUE;
/*-----------------------------------------------------------*/
/* The interrupt service routine - called from the assembly entry point. */
__arm void vSerialISR( void );
/*-----------------------------------------------------------*/
/*
* See the serial2.h header file.
*/
xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength )
{
xComPortHandle xReturn;
UART_InitTypeDef UART_InitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
EIC_IRQInitTypeDef EIC_IRQInitStructure;
/* Create the queues used to hold Rx and Tx characters. */
xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) );
xCharsForTx = xQueueCreate( uxQueueLength + 1, ( unsigned portBASE_TYPE ) sizeof( signed char ) );
/* If the queues were created correctly then setup the serial port
hardware. */
if( ( xRxedChars != serINVALID_QUEUE ) && ( xCharsForTx != serINVALID_QUEUE ) )
{
portENTER_CRITICAL();
{
/* Enable the UART0 Clock. */
MRCC_PeripheralClockConfig( MRCC_Peripheral_UART0, ENABLE );
/* Configure the UART0_Tx as alternate function */
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
GPIO_Init(GPIO0, &GPIO_InitStructure);
/* Configure the UART0_Rx as input floating */
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
GPIO_Init(GPIO0, &GPIO_InitStructure);
/* Configure UART0. */
UART_InitStructure.UART_WordLength = UART_WordLength_8D;
UART_InitStructure.UART_StopBits = UART_StopBits_1;
UART_InitStructure.UART_Parity = UART_Parity_No;
UART_InitStructure.UART_BaudRate = ulWantedBaud;
UART_InitStructure.UART_HardwareFlowControl = UART_HardwareFlowControl_None;
UART_InitStructure.UART_Mode = UART_Mode_Tx_Rx;
UART_InitStructure.UART_TxFIFOLevel = UART_FIFOLevel_1_2; /* FIFO size 16 bytes, FIFO level 8 bytes */
UART_InitStructure.UART_RxFIFOLevel = UART_FIFOLevel_1_2; /* FIFO size 16 bytes, FIFO level 8 bytes */
UART_Init(UART0, &UART_InitStructure);
/* Enable the UART0 */
UART_Cmd(UART0, ENABLE);
/* Configure the IEC for the UART interrupts. */
EIC_IRQInitStructure.EIC_IRQChannelCmd = ENABLE;
EIC_IRQInitStructure.EIC_IRQChannel = UART0_IRQChannel;
EIC_IRQInitStructure.EIC_IRQChannelPriority = 1;
EIC_IRQInit(&EIC_IRQInitStructure);
xQueueEmpty = pdTRUE;
UART_ITConfig( UART0, UART_IT_Transmit | UART_IT_Receive, ENABLE );
}
portEXIT_CRITICAL();
}
else
{
xReturn = ( xComPortHandle ) 0;
}
/* This demo file only supports a single port but we have to return
something to comply with the standard demo header file. */
return xReturn;
}
/*-----------------------------------------------------------*/
signed portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, TickType_t xBlockTime )
{
/* The port handle is not required as this driver only supports one port. */
( void ) pxPort;
/* 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;
}
}
/*-----------------------------------------------------------*/
void vSerialPutString( xComPortHandle pxPort, const signed char * const pcString, unsigned short usStringLength )
{
signed char *pxNext;
/* A couple of parameters that this port does not use. */
( void ) usStringLength;
( void ) pxPort;
/* NOTE: This implementation does not handle the queue being full as no
block time is used! */
/* The port handle is not required as this driver only supports UART0. */
( void ) pxPort;
/* Send each character in the string, one at a time. */
pxNext = ( signed char * ) pcString;
while( *pxNext )
{
xSerialPutChar( pxPort, *pxNext, serNO_BLOCK );
pxNext++;
}
}
/*-----------------------------------------------------------*/
signed portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed char cOutChar, TickType_t xBlockTime )
{
portBASE_TYPE xReturn;
/* Place the character in the queue of characters to be transmitted. */
portENTER_CRITICAL();
{
if( xQueueEmpty == pdTRUE )
{
UART0->DR = cOutChar;
xReturn = pdPASS;
}
else
{
if( xQueueSend( xCharsForTx, &cOutChar, xBlockTime ) != pdPASS )
{
xReturn = pdFAIL;
}
else
{
xReturn = pdPASS;
}
}
xQueueEmpty = pdFALSE;
}
portEXIT_CRITICAL();
return xReturn;
}
/*-----------------------------------------------------------*/
void vSerialClose( xComPortHandle xPort )
{
/* Not supported as not required by the demo application. */
}
/*-----------------------------------------------------------*/
__arm void vSerialISR( void )
{
signed char cChar;
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
do
{
if( UART0->MIS & UART_IT_Transmit )
{
/* The interrupt was caused by the THR becoming empty. Are there any
more characters to transmit? */
if( xQueueReceiveFromISR( xCharsForTx, &cChar, &xHigherPriorityTaskWoken ) == pdTRUE )
{
/* A character was retrieved from the queue so can be sent to the
THR now. */
UART0->DR = cChar;
}
else
{
xQueueEmpty = pdTRUE;
}
UART_ClearITPendingBit( UART0, UART_IT_Transmit );
}
if( UART0->MIS & UART_IT_Receive )
{
/* The interrupt was caused by a character being received. Grab the
character from the RHR and place it in the queue of received
characters. */
cChar = UART0->DR;
xQueueSendFromISR( xRxedChars, &cChar, &xHigherPriorityTaskWoken );
UART_ClearITPendingBit( UART0, UART_IT_Receive );
}
} while( UART0->MIS );
/* If a task was woken by either a character being received or a character
being transmitted then we may need to switch to another task. */
portEND_SWITCHING_ISR( xHigherPriorityTaskWoken );
}
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