\r
/* BASIC INTERRUPT DRIVEN SERIAL PORT DRIVER.\r
*\r
- * This file only supports UART A0 in loopback mode, and has not been tested\r
- * for real UART operation (only loopback mode) so is not guaranteed to have\r
- * a correct baud rate configuration.\r
+ * This is not a proper UART driver. It only supports one port, uses loopback\r
+ * mode, and is used to test interrupts that use the FreeRTOS API as part of\r
+ * a wider test suite. Nor is it intended to show an efficient implementation\r
+ * of a UART interrupt service routine as queues are used to pass individual\r
+ * characters one at a time!\r
*/\r
\r
/* Standard includes. */\r
/* Demo application includes. */\r
#include "serial.h"\r
\r
-/* HAL includes. */\r
-#include "hal_usb.h"\r
-\r
-/* Constants required to setup the hardware. */\r
-#define serTX_AND_RX ( ( unsigned portCHAR ) 0x03 )\r
-\r
/* Misc. constants. */\r
#define serNO_BLOCK ( ( portTickType ) 0 )\r
\r
xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed portCHAR ) );\r
xCharsForTx = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed portCHAR ) );\r
\r
-#if 0\r
/* Reset UART. */\r
- UCA0CTL1 |= UCSWRST;\r
+ UCA1CTL1 |= UCSWRST;\r
\r
/* Use SMCLK. */\r
- UCA0CTL1 = UCSSEL0 | UCSSEL1;\r
+ UCA1CTL1 = UCSSEL0 | UCSSEL1;\r
\r
/* Setup baud rate low byte. */\r
- UCA0BR0 = ( unsigned portCHAR ) ( ulBaudRateCount & ( unsigned portLONG ) 0xff );\r
+ UCA1BR0 = ( unsigned portCHAR ) ( ulBaudRateCount & ( unsigned portLONG ) 0xff );\r
\r
/* Setup baud rate high byte. */\r
ulBaudRateCount >>= 8UL;\r
- UCA0BR1 = ( unsigned portCHAR ) ( ulBaudRateCount & ( unsigned portLONG ) 0xff );\r
+ UCA1BR1 = ( unsigned portCHAR ) ( ulBaudRateCount & ( unsigned portLONG ) 0xff );\r
\r
/* UCLISTEN sets loopback mode! */\r
- UCA0STAT = UCLISTEN;\r
+ UCA1STAT = UCLISTEN;\r
\r
- /* Clear interrupts. */\r
-// UCA0IFG = 0;\r
- \r
/* Enable interrupts. */\r
- UCA0IE |= UCRXIE;\r
+ UCA1IE |= UCRXIE;\r
\r
/* Take out of reset. */\r
- UCA0CTL1 &= ~UCSWRST;\r
-#else\r
- USB_PORT_SEL |= USB_PIN_RXD + USB_PIN_TXD;\r
- USB_PORT_DIR |= USB_PIN_TXD;\r
- USB_PORT_DIR &= ~USB_PIN_RXD;\r
- \r
- UCA1CTL1 |= UCSWRST; //Reset State\r
- UCA1CTL0 = UCMODE_0;\r
- \r
- UCA1CTL0 &= ~UC7BIT; // 8bit char\r
- UCA1CTL1 |= UCSSEL_2;\r
-// UCA1BR0 = 16; // 8Mhz/57600=138\r
-// UCA1BR1 = 1;\r
- /* Setup baud rate low byte. */\r
- UCA0BR0 = ( unsigned portCHAR ) ( ulBaudRateCount & ( unsigned portLONG ) 0xff );\r
-\r
- /* Setup baud rate high byte. */\r
- ulBaudRateCount >>= 8UL;\r
- UCA0BR1 = ( unsigned portCHAR ) ( ulBaudRateCount & ( unsigned portLONG ) 0xff );\r
-\r
- UCA1MCTL = 0xE;\r
- UCA1CTL1 &= ~UCSWRST;\r
- UCA1IE |= UCRXIE;\r
-#endif\r
+ UCA1CTL1 &= ~UCSWRST;\r
}\r
portEXIT_CRITICAL();\r
\r
- /* Unlike other ports, this serial code does not allow for more than one\r
- com port. We therefore don't return a pointer to a port structure and can\r
- instead just return NULL. */\r
+ /* Note the comments at the top of this file about this not being a generic\r
+ UART driver. */\r
return NULL;\r
}\r
/*-----------------------------------------------------------*/\r
{\r
signed portBASE_TYPE xReturn;\r
\r
+ /* Send the next character to the queue of characters waiting transmission,\r
+ then enable the UART Tx interrupt, just in case UART transmission has already\r
+ completed and switched itself off. */\r
xReturn = xQueueSend( xCharsForTx, &cOutChar, xBlockTime );\r
- UCA0IE |= UCTXIE;\r
+ UCA1IE |= UCTXIE;\r
\r
return xReturn;\r
}\r
/*-----------------------------------------------------------*/\r
-char cTxedBytes[ 512 ];\r
-char cRxedBytes[ 512 ];\r
-volatile int xIndex = 0;\r
-volatile int xIndex2 = 0;\r
\r
-#pragma vector=USCI_A0_VECTOR\r
-static __interrupt void prvUSCI_A0_ISR( void )\r
+#pragma vector=USCI_A1_VECTOR\r
+static __interrupt void prvUSCI_A1_ISR( void )\r
{\r
signed portCHAR cChar;\r
portBASE_TYPE xTaskWoken = pdFALSE;\r
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;\r
\r
- while( UCA0IFG & UCRXIFG )\r
+ while( ( UCA1IFG & UCRXIFG ) != 0 )\r
{\r
/* Get the character from the UART and post it on the queue of Rxed\r
characters. */\r
- cChar = UCA0RXBUF;\r
-\r
-if( xIndex2 < 500 )\r
-{\r
- cRxedBytes[ xIndex2++ ] = cChar;\r
-}\r
-\r
+ cChar = UCA1RXBUF;\r
xQueueSendFromISR( xRxedChars, &cChar, &xHigherPriorityTaskWoken );\r
}\r
\r
- if( UCA0IFG & UCTXIFG )\r
+ /* If there is a Tx interrupt pending and the tx interrupts are enabled. */\r
+ if( ( UCA1IFG & UCTXIFG ) != 0 )\r
{\r
/* The previous character has been transmitted. See if there are any\r
further characters waiting transmission. */\r
if( xQueueReceiveFromISR( xCharsForTx, &cChar, &xTaskWoken ) == pdTRUE )\r
{\r
-if( xIndex < 500 )\r
-{\r
- cTxedBytes[ xIndex++ ] = cChar;\r
-}\r
-\r
/* There was another character queued - transmit it now. */\r
- UCA0TXBUF = cChar;\r
+ UCA1TXBUF = cChar;\r
}\r
else\r
{\r
/* There were no other characters to transmit - disable the Tx\r
interrupt. */\r
- UCA0IE &= ~UCTXIE;\r
+ UCA1IE &= ~UCTXIE;\r
}\r
}\r
\r
- __bic_SR_register_on_exit( SCG1 + SCG0 + OSCOFF + CPUOFF ); \r
+ __bic_SR_register_on_exit( SCG1 + SCG0 + OSCOFF + CPUOFF );\r
+ \r
+ /* If writing to a queue caused a task to unblock, and the unblocked task\r
+ has a priority equal to or above the task that this interrupt interrupted,\r
+ then lHigherPriorityTaskWoken will have been set to pdTRUE internally within\r
+ xQueuesendFromISR(), and portEND_SWITCHING_ISR() will ensure that this\r
+ interrupt returns directly to the higher priority unblocked task.\r
+ \r
+ THIS MUST BE THE LAST THING DONE IN THE ISR. */ \r
portYIELD_FROM_ISR( xHigherPriorityTaskWoken );\r
}\r
\r
projects / freertos / blobdiff