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29 BASIC INTERRUPT DRIVEN SERIAL PORT DRIVER FOR UART0.
33 /*-----------------------------------------------------------
34 * Components that can be compiled to either ARM or THUMB mode are
35 * contained in this file.c The ISR routines, which can only be compiled
36 * to ARM mode, are contained in serialISR.c.
37 *----------------------------------------------------------*/
41 /* Library includes. */
47 /* Scheduler includes. */
51 /* Demo application includes. */
54 #define serINVALID_QUEUE ( ( QueueHandle_t ) 0 )
55 #define serNO_BLOCK ( ( TickType_t ) 0 )
57 /*-----------------------------------------------------------*/
59 /* Queues used to hold received characters, and characters waiting to be
61 static QueueHandle_t xRxedChars;
62 static QueueHandle_t xCharsForTx;
64 static volatile portBASE_TYPE xQueueEmpty = pdTRUE;
66 /*-----------------------------------------------------------*/
68 /* The interrupt service routine - called from the assembly entry point. */
69 void vSerialISR( void );
70 void vConfigureQueues( QueueHandle_t xQForRx, QueueHandle_t xQForTx, volatile portBASE_TYPE *pxEmptyFlag );
72 /*-----------------------------------------------------------*/
75 * See the serial2.h header file.
77 xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength )
79 xComPortHandle xReturn;
80 UART_InitTypeDef UART_InitStructure;
81 GPIO_InitTypeDef GPIO_InitStructure;
82 EIC_IRQInitTypeDef EIC_IRQInitStructure;
84 /* Create the queues used to hold Rx and Tx characters. */
85 xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) );
86 xCharsForTx = xQueueCreate( uxQueueLength + 1, ( unsigned portBASE_TYPE ) sizeof( signed char ) );
88 /* If the queues were created correctly then setup the serial port
90 if( ( xRxedChars != serINVALID_QUEUE ) && ( xCharsForTx != serINVALID_QUEUE ) )
93 vConfigureQueues( xRxedChars, xCharsForTx, &xQueueEmpty );
97 /* Enable the UART0 Clock. */
98 MRCC_PeripheralClockConfig( MRCC_Peripheral_UART0, ENABLE );
100 /* Configure the UART0_Tx as alternate function */
101 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
102 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11;
103 GPIO_Init(GPIO0, &GPIO_InitStructure);
105 /* Configure the UART0_Rx as input floating */
106 GPIO_InitStructure.GPIO_Mode = GPIO_Mode_IN_FLOATING;
107 GPIO_InitStructure.GPIO_Pin = GPIO_Pin_10;
108 GPIO_Init(GPIO0, &GPIO_InitStructure);
110 /* Configure UART0. */
111 UART_InitStructure.UART_WordLength = UART_WordLength_8D;
112 UART_InitStructure.UART_StopBits = UART_StopBits_1;
113 UART_InitStructure.UART_Parity = UART_Parity_No;
114 UART_InitStructure.UART_BaudRate = ulWantedBaud;
115 UART_InitStructure.UART_HardwareFlowControl = UART_HardwareFlowControl_None;
116 UART_InitStructure.UART_Mode = UART_Mode_Tx_Rx;
117 UART_InitStructure.UART_TxFIFOLevel = UART_FIFOLevel_1_2; /* FIFO size 16 bytes, FIFO level 8 bytes */
118 UART_InitStructure.UART_RxFIFOLevel = UART_FIFOLevel_1_2; /* FIFO size 16 bytes, FIFO level 8 bytes */
119 UART_Init(UART0, &UART_InitStructure);
121 /* Enable the UART0 */
122 UART_Cmd(UART0, ENABLE);
124 /* Configure the IEC for the UART interrupts. */
125 EIC_IRQInitStructure.EIC_IRQChannelCmd = ENABLE;
126 EIC_IRQInitStructure.EIC_IRQChannel = UART0_IRQChannel;
127 EIC_IRQInitStructure.EIC_IRQChannelPriority = 1;
128 EIC_IRQInit(&EIC_IRQInitStructure);
130 xQueueEmpty = pdTRUE;
131 UART_ITConfig( UART0, UART_IT_Transmit | UART_IT_Receive, ENABLE );
137 xReturn = ( xComPortHandle ) 0;
140 /* This demo file only supports a single port but we have to return
141 something to comply with the standard demo header file. */
144 /*-----------------------------------------------------------*/
146 signed portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, TickType_t xBlockTime )
148 /* The port handle is not required as this driver only supports one port. */
151 /* Get the next character from the buffer. Return false if no characters
152 are available, or arrive before xBlockTime expires. */
153 if( xQueueReceive( xRxedChars, pcRxedChar, xBlockTime ) )
162 /*-----------------------------------------------------------*/
164 void vSerialPutString( xComPortHandle pxPort, const signed char * const pcString, unsigned short usStringLength )
168 /* A couple of parameters that this port does not use. */
169 ( void ) usStringLength;
172 /* NOTE: This implementation does not handle the queue being full as no
173 block time is used! */
175 /* The port handle is not required as this driver only supports UART0. */
178 /* Send each character in the string, one at a time. */
179 pxNext = ( signed char * ) pcString;
182 xSerialPutChar( pxPort, *pxNext, serNO_BLOCK );
186 /*-----------------------------------------------------------*/
188 signed portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed char cOutChar, TickType_t xBlockTime )
190 portBASE_TYPE xReturn;
192 /* Place the character in the queue of characters to be transmitted. */
193 portENTER_CRITICAL();
195 if( xQueueEmpty == pdTRUE )
197 UART0->DR = cOutChar;
202 if( xQueueSend( xCharsForTx, &cOutChar, xBlockTime ) != pdPASS )
212 xQueueEmpty = pdFALSE;
218 /*-----------------------------------------------------------*/
220 void vSerialClose( xComPortHandle xPort )
222 /* Not supported as not required by the demo application. */
224 /*-----------------------------------------------------------*/