/* | |
* FreeRTOS Kernel V10.3.0 | |
* 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 UART0. | |
*/ | |
/* Scheduler includes. */ | |
#include "FreeRTOS.h" | |
#include "queue.h" | |
#include "semphr.h" | |
/* Library includes. */ | |
#include "stm32f10x_lib.h" | |
/* Demo application includes. */ | |
#include "serial.h" | |
/*-----------------------------------------------------------*/ | |
/* Misc defines. */ | |
#define serINVALID_QUEUE ( ( QueueHandle_t ) 0 ) | |
#define serNO_BLOCK ( ( TickType_t ) 0 ) | |
#define serTX_BLOCK_TIME ( 40 / portTICK_PERIOD_MS ) | |
/*-----------------------------------------------------------*/ | |
/* The queue used to hold received characters. */ | |
static QueueHandle_t xRxedChars; | |
static QueueHandle_t xCharsForTx; | |
/*-----------------------------------------------------------*/ | |
/* UART interrupt handler. */ | |
void vUARTInterruptHandler( void ); | |
/*-----------------------------------------------------------*/ | |
/* | |
* See the serial2.h header file. | |
*/ | |
xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength ) | |
{ | |
xComPortHandle xReturn; | |
USART_InitTypeDef USART_InitStructure; | |
NVIC_InitTypeDef NVIC_InitStructure; | |
GPIO_InitTypeDef GPIO_InitStructure; | |
/* Create the queues used to hold Rx/Tx characters. */ | |
xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) ); | |
xCharsForTx = xQueueCreate( uxQueueLength + 1, ( unsigned portBASE_TYPE ) sizeof( signed char ) ); | |
/* If the queue/semaphore was created correctly then setup the serial port | |
hardware. */ | |
if( ( xRxedChars != serINVALID_QUEUE ) && ( xCharsForTx != serINVALID_QUEUE ) ) | |
{ | |
/* Enable USART1 clock */ | |
RCC_APB2PeriphClockCmd( RCC_APB2Periph_USART1 | RCC_APB2Periph_GPIOA, ENABLE ); | |
/* Configure USART1 Rx (PA10) as input floating */ | |
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10; | |
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING; | |
GPIO_Init( GPIOA, &GPIO_InitStructure ); | |
/* Configure USART1 Tx (PA9) as alternate function push-pull */ | |
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_9; | |
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz; | |
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; | |
GPIO_Init( GPIOA, &GPIO_InitStructure ); | |
USART_InitStructure.USART_BaudRate = ulWantedBaud; | |
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_InitStructure.USART_Clock = USART_Clock_Disable; | |
USART_InitStructure.USART_CPOL = USART_CPOL_Low; | |
USART_InitStructure.USART_CPHA = USART_CPHA_2Edge; | |
USART_InitStructure.USART_LastBit = USART_LastBit_Disable; | |
USART_Init( USART1, &USART_InitStructure ); | |
USART_ITConfig( USART1, USART_IT_RXNE, ENABLE ); | |
NVIC_InitStructure.NVIC_IRQChannel = USART1_IRQChannel; | |
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = configLIBRARY_KERNEL_INTERRUPT_PRIORITY; | |
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0; | |
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE; | |
NVIC_Init( &NVIC_InitStructure ); | |
USART_Cmd( USART1, ENABLE ); | |
} | |
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 UART1. */ | |
( 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 ) | |
{ | |
signed portBASE_TYPE xReturn; | |
if( xQueueSend( xCharsForTx, &cOutChar, xBlockTime ) == pdPASS ) | |
{ | |
xReturn = pdPASS; | |
USART_ITConfig( USART1, USART_IT_TXE, ENABLE ); | |
} | |
else | |
{ | |
xReturn = pdFAIL; | |
} | |
return xReturn; | |
} | |
/*-----------------------------------------------------------*/ | |
void vSerialClose( xComPortHandle xPort ) | |
{ | |
/* Not supported as not required by the demo application. */ | |
} | |
/*-----------------------------------------------------------*/ | |
void vUARTInterruptHandler( void ) | |
{ | |
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE; | |
char cChar; | |
if( USART_GetITStatus( USART1, USART_IT_TXE ) == SET ) | |
{ | |
/* 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. */ | |
USART_SendData( USART1, cChar ); | |
} | |
else | |
{ | |
USART_ITConfig( USART1, USART_IT_TXE, DISABLE ); | |
} | |
} | |
if( USART_GetITStatus( USART1, USART_IT_RXNE ) == SET ) | |
{ | |
cChar = USART_ReceiveData( USART1 ); | |
xQueueSendFromISR( xRxedChars, &cChar, &xHigherPriorityTaskWoken ); | |
} | |
portEND_SWITCHING_ISR( xHigherPriorityTaskWoken ); | |
} | |