2 FreeRTOS.org V4.7.0 - Copyright (C) 2003-2007 Richard Barry.
\r
4 This file is part of the FreeRTOS.org distribution.
\r
6 FreeRTOS.org is free software; you can redistribute it and/or modify
\r
7 it under the terms of the GNU General Public License as published by
\r
8 the Free Software Foundation; either version 2 of the License, or
\r
9 (at your option) any later version.
\r
11 FreeRTOS.org is distributed in the hope that it will be useful,
\r
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
\r
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
\r
14 GNU General Public License for more details.
\r
16 You should have received a copy of the GNU General Public License
\r
17 along with FreeRTOS.org; if not, write to the Free Software
\r
18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
\r
20 A special exception to the GPL can be applied should you wish to distribute
\r
21 a combined work that includes FreeRTOS.org, without being obliged to provide
\r
22 the source code for any proprietary components. See the licensing section
\r
23 of http://www.FreeRTOS.org for full details of how and when the exception
\r
26 ***************************************************************************
\r
27 See http://www.FreeRTOS.org for documentation, latest information, license
\r
28 and contact details. Please ensure to read the configuration and relevant
\r
29 port sections of the online documentation.
\r
31 Also see http://www.SafeRTOS.com a version that has been certified for use
\r
32 in safety critical systems, plus commercial licensing, development and
\r
34 ***************************************************************************
\r
38 Sample interrupt driven USB device driver. This is a minimal implementation
\r
39 for demonstration only. Although functional, it is not a full and compliant
\r
42 The USB device enumerates as a simple 3 axis joystick, and once configured
\r
43 transmits 3 axis of data which can be viewed from the USB host machine.
\r
45 This file implements the USB interrupt service routine, and a demo FreeRTOS
\r
46 task. The interrupt service routine handles the USB hardware - taking a
\r
47 snapshot of the USB status at the point of the interrupt. The task receives
\r
48 the status information from the interrupt for processing at the task level.
\r
50 See the FreeRTOS.org WEB documentation for more information.
\r
56 + Descriptors that have a length that is an exact multiple of usbFIFO_LENGTH
\r
57 can now be transmitted. To this end an extra parameter has been
\r
58 added to the prvSendControlData() function, and the state
\r
59 eSENDING_EVEN_DESCRIPTOR has been introduced. Thanks to Scott Miller for
\r
60 assisting with this contribution.
\r
64 + Replaced the duplicated RX_DATA_BK0 in the interrupt mask with the
\r
68 /* Standard includes. */
\r
71 /* Demo board includes. */
\r
74 /* Scheduler includes. */
\r
75 #include "FreeRTOS.h"
\r
80 /* Descriptor type definitions. */
\r
81 #define usbDESCRIPTOR_TYPE_DEVICE ( 0x01 )
\r
82 #define usbDESCRIPTOR_TYPE_CONFIGURATION ( 0x02 )
\r
83 #define usbDESCRIPTOR_TYPE_STRING ( 0x03 )
\r
85 /* USB request type definitions. */
\r
86 #define usbGET_REPORT_REQUEST ( 0x01 )
\r
87 #define usbGET_IDLE_REQUEST ( 0x02 )
\r
88 #define usbGET_PROTOCOL_REQUEST ( 0x03 )
\r
89 #define usbSET_REPORT_REQUEST ( 0x09 )
\r
90 #define usbSET_IDLE_REQUEST ( 0x0A )
\r
91 #define usbSET_PROTOCOL_REQUEST ( 0x0B )
\r
92 #define usbGET_CONFIGURATION_REQUEST ( 0x08 )
\r
93 #define usbGET_STATUS_REQUEST ( 0x00 )
\r
94 #define usbCLEAR_FEATURE_REQUEST ( 0x01 )
\r
95 #define usbSET_FEATURE_REQUEST ( 0x03 )
\r
96 #define usbSET_ADDRESS_REQUEST ( 0x05 )
\r
97 #define usbGET_DESCRIPTOR_REQUEST ( 0x06 )
\r
98 #define usbSET_CONFIGURATION_REQUEST ( 0x09 )
\r
99 #define usbGET_INTERFACE_REQUEST ( 0x0A )
\r
100 #define usbSET_INTERFACE_REQUEST ( 0x0B )
\r
103 /* Misc USB definitions. */
\r
104 #define usbDEVICE_CLASS_VENDOR_SPECIFIC ( 0xFF )
\r
105 #define usbBUS_POWERED ( 0x80 )
\r
106 #define usbHID_REPORT_DESCRIPTOR ( 0x22 )
\r
107 #define AT91C_UDP_TRANSCEIVER_ENABLE ( *( ( unsigned long * ) 0xfffb0074 ) )
\r
109 /* Index to the various string. */
\r
110 #define usbLANGUAGE_STRING ( 0 )
\r
111 #define usbMANUFACTURER_STRING ( 1 )
\r
112 #define usbPRODUCT_STRING ( 2 )
\r
113 #define usbCONFIGURATION_STRING ( 3 )
\r
114 #define usbINTERFACE_STRING ( 4 )
\r
116 /* Data indexes for reading the request from the xISRStatus.ucFifoData[]
\r
117 into xUSB_REQUEST. The data order is designed for speed - so looks a
\r
119 #define usbREQUEST_TYPE_INDEX ( 7 )
\r
120 #define usbREQUEST_INDEX ( 6 )
\r
121 #define usbVALUE_HIGH_BYTE ( 4 )
\r
122 #define usbVALUE_LOW_BYTE ( 5 )
\r
123 #define usbINDEX_HIGH_BYTE ( 2 )
\r
124 #define usbINDEX_LOW_BYTE ( 3 )
\r
125 #define usbLENGTH_HIGH_BYTE ( 0 )
\r
126 #define usbLENGTH_LOW_BYTE ( 1 )
\r
128 /* Misc application definitions. */
\r
129 #define usbINTERRUPT_PRIORITY ( 3 )
\r
130 #define usbQUEUE_LENGTH ( 0x3 ) /* Must have all bits set! */
\r
131 #define usbFIFO_LENGTH ( ( unsigned portLONG ) 8 )
\r
132 #define usbEND_POINT_0 ( 0 )
\r
133 #define usbEND_POINT_1 ( 1 )
\r
134 #define usbXUP ( 1 )
\r
135 #define usbXDOWN ( 2 )
\r
136 #define usbYUP ( 3 )
\r
137 #define usbYDOWN ( 4 )
\r
138 #define usbMAX_COORD ( 120 )
\r
139 #define usbMAX_TX_MESSAGE_SIZE ( 128 )
\r
140 #define usbRX_COUNT_MASK ( ( unsigned portLONG ) 0x7ff )
\r
141 #define AT91C_UDP_STALLSENT AT91C_UDP_ISOERROR
\r
142 #define usbSHORTEST_DELAY ( ( portTickType ) 1 )
\r
143 #define usbINIT_DELAY ( ( portTickType ) 500 / portTICK_RATE_MS )
\r
144 #define usbSHORT_DELAY ( ( portTickType ) 50 / portTICK_RATE_MS )
\r
145 #define usbEND_POINT_RESET_MASK ( ( unsigned portLONG ) 0x0f )
\r
146 #define usbDATA_INC ( ( portCHAR ) 5 )
\r
147 #define usbEXPECTED_NUMBER_OF_BYTES ( ( unsigned portLONG ) 8 )
\r
149 /* Control request types. */
\r
150 #define usbSTANDARD_DEVICE_REQUEST ( 0 )
\r
151 #define usbSTANDARD_INTERFACE_REQUEST ( 1 )
\r
152 #define usbSTANDARD_END_POINT_REQUEST ( 2 )
\r
153 #define usbCLASS_INTERFACE_REQUEST ( 5 )
\r
155 /*-----------------------------------------------------------*/
\r
157 /* Structure used to take a snapshot of the USB status from within the ISR. */
\r
158 typedef struct X_ISR_STATUS
\r
160 unsigned portLONG ulISR;
\r
161 unsigned portLONG ulCSR0;
\r
162 unsigned portCHAR ucFifoData[ 8 ];
\r
165 /* Structure used to hold the received requests. */
\r
168 unsigned portCHAR ucReqType;
\r
169 unsigned portCHAR ucRequest;
\r
170 unsigned portSHORT usValue;
\r
171 unsigned portSHORT usIndex;
\r
172 unsigned portSHORT usLength;
\r
181 eSENDING_EVEN_DESCRIPTOR,
\r
185 /* Structure used to control the data being sent to the host. */
\r
188 unsigned portCHAR ucTxBuffer[ usbMAX_TX_MESSAGE_SIZE ];
\r
189 unsigned portLONG ulNextCharIndex;
\r
190 unsigned portLONG ulTotalDataLength;
\r
193 /*-----------------------------------------------------------*/
\r
196 * The USB interrupt service routine. This takes a snapshot of the USB
\r
197 * device at the time of the interrupt, clears the interrupts, and posts
\r
198 * the data to the USB processing task.
\r
200 __arm void vUSB_ISR( void );
\r
203 * Called after the bus reset interrupt - this function readies all the
\r
204 * end points for communication.
\r
206 static void prvResetEndPoints( void );
\r
209 * Setup the USB hardware, install the interrupt service routine and
\r
210 * initialise all the state variables.
\r
212 static void vInitUSBInterface( void );
\r
215 * Decode and act upon an interrupt generated by the control end point.
\r
217 static void prvProcessEndPoint0Interrupt( xISRStatus *pxMessage );
\r
220 * For simplicity requests are separated into device, interface, class
\r
221 * interface and end point requests.
\r
223 * Decode and handle standard device requests originating on the control
\r
226 static void prvHandleStandardDeviceRequest( xUSB_REQUEST *pxRequest );
\r
229 * For simplicity requests are separated into device, interface, class
\r
230 * interface and end point requests.
\r
232 * Decode and handle standard interface requests originating on the control
\r
235 static void prvHandleStandardInterfaceRequest( xUSB_REQUEST *pxRequest );
\r
238 * For simplicity requests are separated into device, interface, class
\r
239 * interface and end point requests.
\r
241 * Decode and handle standard end point requests originating on the control
\r
244 static void prvHandleStandardEndPointRequest( xUSB_REQUEST *pxRequest );
\r
247 * For simplicity requests are separated into device, interface, class
\r
248 * interface and end point requests.
\r
250 * Decode and handle the class interface requests.
\r
252 static void prvHandleClassInterfaceRequest( xUSB_REQUEST *pxRequest );
\r
255 * Setup the Tx buffer to send data in response to a control request.
\r
257 * The data to be transmitted is buffered, the state variables are updated,
\r
258 * then prvSendNextSegment() is called to start the transmission off. Once
\r
259 * the first segment has been sent the remaining segments are transmitted
\r
260 * in response to TXCOMP interrupts until the entire buffer has been
\r
263 static void prvSendControlData( unsigned portCHAR *pucData, unsigned portSHORT usRequestedLength, unsigned portLONG ulLengthLeftToSend, portLONG lSendingDescriptor );
\r
266 * Examine the Tx buffer to see if there is any more data to be transmitted.
\r
268 * If there is data to be transmitted then send the next segment. A segment
\r
269 * can have a maximum of 8 bytes (this is defined as the maximum for the end
\r
270 * point by the descriptor). The final segment may be less than 8 bytes if
\r
271 * the total data length was not an exact multiple of 8.
\r
273 static void prvSendNextSegment( void );
\r
276 * A stall condition is forced each time the host makes a request that is not
\r
277 * supported by this minimal implementation.
\r
279 * A stall is forced by setting the appropriate bit in the end points control
\r
280 * and status register.
\r
282 static void prvSendStall( void );
\r
285 * A NULL (or zero length packet) is transmitted in acknowledge the reception
\r
286 * of certain events from the host.
\r
288 static void prvUSBTransmitNull( void );
\r
291 * When the host requests a descriptor this function is called to determine
\r
292 * which descriptor is being requested and start its transmission.
\r
294 static void prvGetStandardInterfaceDescriptor( xUSB_REQUEST *pxRequest );
\r
297 * This demo USB device enumerates as a simple 3 axis joystick. Once
\r
298 * configured this function is periodically called to generate some sample
\r
301 * The x and y axis are made to move in a square. The z axis is made to
\r
302 * repeatedly increment up to its maximum.
\r
304 static void prvTransmitSampleValues( void );
\r
307 * The created task to handle the USB demo functionality.
\r
309 void vUSBDemoTask( void *pvParameters );
\r
311 /*-----------------------------------------------------------*/
\r
314 - DESCRIPTOR DEFINITIONS -
\r
317 /* String descriptors used during the enumeration process.
\r
318 These take the form:
\r
321 Length of descriptor,
\r
326 const portCHAR pxLanguageStringDescriptor[] =
\r
329 usbDESCRIPTOR_TYPE_STRING,
\r
333 const portCHAR pxManufacturerStringDescriptor[] =
\r
336 usbDESCRIPTOR_TYPE_STRING,
\r
348 const portCHAR pxProductStringDescriptor[] =
\r
351 usbDESCRIPTOR_TYPE_STRING,
\r
376 const portCHAR pxConfigurationStringDescriptor[] =
\r
379 usbDESCRIPTOR_TYPE_STRING,
\r
401 const portCHAR pxInterfaceStringDescriptor[] =
\r
404 usbDESCRIPTOR_TYPE_STRING,
\r
422 /* Enumeration descriptors. */
\r
423 const portCHAR pxReportDescriptor[] =
\r
425 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */
\r
426 0x09, 0x04, /* USAGE (Joystick) */
\r
427 0xa1, 0x01, /* COLLECTION (Application) */
\r
428 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */
\r
429 0x09, 0x01, /* USAGE (Pointer) */
\r
430 0xa1, 0x00, /* COLLECTION (Physical) */
\r
431 0x09, 0x30, /* USAGE (X) */
\r
432 0x09, 0x31, /* USAGE (Y) */
\r
433 0x09, 0x32, /* USAGE (Z) */
\r
434 0x15, 0x81, /* LOGICAL_MINIMUM (-127) */
\r
435 0x25, 0x7f, /* LOGICAL_MAXIMUM (127) */
\r
436 0x75, 0x08, /* REPORT_SIZE (8) */
\r
437 0x95, 0x03, /* REPORT_COUNT (3) */
\r
438 0x81, 0x02, /* INPUT (Data,Var,Abs) */
\r
439 0xc0, /* END_COLLECTION */
\r
440 0xc0 /* END_COLLECTION */
\r
443 const char pxDeviceDescriptor[] =
\r
445 /* Device descriptor */
\r
446 0x12, /* bLength */
\r
447 0x01, /* bDescriptorType */
\r
448 0x10, 0x01, /* bcdUSBL */
\r
449 usbDEVICE_CLASS_VENDOR_SPECIFIC, /* bDeviceClass: */
\r
450 0x00, /* bDeviceSubclass: */
\r
451 0x00, /* bDeviceProtocol: */
\r
452 0x08, /* bMaxPacketSize0 */
\r
453 0xFF, 0xFF, /* idVendorL */
\r
454 0x01, 0x00, /* idProductL */
\r
455 0x00, 0x01, /* bcdDeviceL */
\r
456 usbMANUFACTURER_STRING, /* iManufacturer */
\r
457 usbPRODUCT_STRING, /* iProduct */
\r
458 0x00, /* SerialNumber */
\r
459 0x01 /* bNumConfigs */
\r
462 const char pxConfigDescriptor[] = {
\r
463 /* Configuration 1 descriptor */
\r
464 0x09, /* CbLength */
\r
465 0x02, /* CbDescriptorType */
\r
466 0x22, 0x00, /* CwTotalLength 2 EP + Control */
\r
467 0x01, /* CbNumInterfaces */
\r
468 0x01, /* CbConfigurationValue */
\r
469 usbCONFIGURATION_STRING,/* CiConfiguration */
\r
470 usbBUS_POWERED, /* CbmAttributes Bus powered + Remote Wakeup*/
\r
471 0x32, /* CMaxPower: 100mA */
\r
473 /* Joystick Interface Descriptor Requirement */
\r
474 0x09, /* bLength */
\r
475 0x04, /* bDescriptorType */
\r
476 0x00, /* bInterfaceNumber */
\r
477 0x00, /* bAlternateSetting */
\r
478 0x01, /* bNumEndpoints */
\r
479 0x03, /* bInterfaceClass: HID code */
\r
480 0x00, /* bInterfaceSubclass */
\r
481 0x00, /* bInterfaceProtocol */
\r
482 usbINTERFACE_STRING,/* iInterface */
\r
484 /* HID Descriptor */
\r
485 0x09, /* bLength */
\r
486 0x21, /* bDescriptor type: HID Descriptor Type */
\r
487 0x00, 0x01, /* bcdHID */
\r
488 0x00, /* bCountryCode */
\r
489 0x01, /* bNumDescriptors */
\r
490 usbHID_REPORT_DESCRIPTOR, /* bDescriptorType */
\r
491 sizeof( pxReportDescriptor ), 0x00, /* wItemLength */
\r
493 /* Endpoint 1 descriptor */
\r
494 0x07, /* bLength */
\r
495 0x05, /* bDescriptorType */
\r
496 0x81, /* bEndpointAddress, Endpoint 01 - IN */
\r
497 0x03, /* bmAttributes INT */
\r
498 0x03, 0x00, /* wMaxPacketSize: 3 bytes (x, y, z) */
\r
499 0x0A /* bInterval */
\r
502 /*-----------------------------------------------------------*/
\r
504 /* File scope state variables. */
\r
505 static unsigned portCHAR ucUSBConfig = ( unsigned portCHAR ) 0;
\r
506 static unsigned portLONG ulReceivedAddress = ( unsigned portLONG ) 0;
\r
507 static eDRIVER_STATE eDriverState = eNOTHING;
\r
509 /* Array in which the USB interrupt status is passed between the ISR and task. */
\r
510 static xISRStatus xISRMessages[ usbQUEUE_LENGTH + 1 ];
\r
512 /* Structure used to control the characters being sent to the host. */
\r
513 static xTX_MESSAGE pxCharsForTx;
\r
515 /* Queue used to pass messages between the ISR and the task. */
\r
516 static xQueueHandle xUSBInterruptQueue;
\r
518 /* ISR entry has to be written in the asm file as we want a context switch
\r
519 to occur from within the ISR. See the port documentation on the FreeRTOS.org
\r
520 WEB site for more information. */
\r
521 extern void vUSBISREntry( void );
\r
523 /*-----------------------------------------------------------*/
\r
525 /* Macros to manipulate the control and status registers. These registers
\r
526 cannot be accessed using a direct read modify write operation outside of the
\r
527 ISR as some bits are left unchanged by writing with a 0, and some are left
\r
528 unchanged by writing with a 1. */
\r
530 #define usbINT_CLEAR_MASK (AT91C_UDP_TXCOMP | AT91C_UDP_STALLSENT | AT91C_UDP_RXSETUP | AT91C_UDP_RX_DATA_BK0 | AT91C_UDP_RX_DATA_BK1 )
\r
532 #define usbCSR_SET_BIT( pulValueNow, ulBit ) \
\r
534 /* Set TXCOMP, RX_DATA_BK0, RXSETUP, */ \
\r
535 /* STALLSENT and RX_DATA_BK1 to 1 so the */ \
\r
536 /* write has no effect. */ \
\r
537 ( * ( ( unsigned portLONG * ) pulValueNow ) ) |= ( unsigned portLONG ) 0x4f; \
\r
539 /* Clear the FORCE_STALL and TXPKTRDY bits */ \
\r
540 /* so the write has no effect. */ \
\r
541 ( * ( ( unsigned portLONG * ) pulValueNow ) ) &= ( unsigned portLONG ) 0xffffffcf; \
\r
543 /* Set whichever bit we want set. */ \
\r
544 ( * ( ( unsigned portLONG * ) pulValueNow ) ) |= ( ulBit ); \
\r
547 #define usbCSR_CLEAR_BIT( pulValueNow, ulBit ) \
\r
549 /* Set TXCOMP, RX_DATA_BK0, RXSETUP, */ \
\r
550 /* STALLSENT and RX_DATA_BK1 to 1 so the */ \
\r
551 /* write has no effect. */ \
\r
552 ( * ( ( unsigned portLONG * ) pulValueNow ) ) |= ( unsigned portLONG ) 0x4f; \
\r
554 /* Clear the FORCE_STALL and TXPKTRDY bits */ \
\r
555 /* so the write has no effect. */ \
\r
556 ( * ( ( unsigned portLONG * ) pulValueNow ) ) &= ( unsigned portLONG ) 0xffffffcf; \
\r
558 /* Clear whichever bit we want clear. */ \
\r
559 ( * ( ( unsigned portLONG * ) pulValueNow ) ) &= ( ~ulBit ); \
\r
562 /*-----------------------------------------------------------*/
\r
564 __arm void vUSB_ISR( void )
\r
566 portBASE_TYPE xTaskWokenByPost = pdFALSE;
\r
567 static volatile unsigned portLONG ulNextMessage = 0;
\r
568 xISRStatus *pxMessage;
\r
569 unsigned portLONG ulTemp, ulRxBytes;
\r
571 /* Take the next message from the queue. Note that usbQUEUE_LENGTH *must*
\r
572 be all 1's, as in 0x01, 0x03, 0x07, etc. */
\r
573 pxMessage = &( xISRMessages[ ( ulNextMessage & usbQUEUE_LENGTH ) ] );
\r
576 /* Take a snapshot of the current USB state for processing at the task
\r
578 pxMessage->ulISR = AT91C_BASE_UDP->UDP_ISR;
\r
579 pxMessage->ulCSR0 = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
581 /* Clear the interrupts from the ICR register. The bus end interrupt is
\r
582 cleared separately as it does not appear in the mask register. */
\r
583 AT91C_BASE_UDP->UDP_ICR = AT91C_BASE_UDP->UDP_IMR | AT91C_UDP_ENDBUSRES;
\r
585 /* If there are bytes in the FIFO then we have to retrieve them here.
\r
586 Ideally this would be done at the task level. However we need to clear the
\r
587 RXSETUP interrupt before leaving the ISR, and this may cause the data in
\r
588 the FIFO to be overwritten. Also the DIR bit has to be changed before the
\r
589 RXSETUP bit is cleared (as per the SAM7 manual). */
\r
590 ulTemp = pxMessage->ulCSR0;
\r
592 /* Are there any bytes in the FIFO? */
\r
593 ulRxBytes = ulTemp >> 16;
\r
594 ulRxBytes &= usbRX_COUNT_MASK;
\r
596 /* With this minimal implementation we are only interested in receiving
\r
597 setup bytes on the control end point. */
\r
598 if( ( ulRxBytes > 0 ) && ( ulTemp & AT91C_UDP_RXSETUP ) )
\r
600 /* Take off 1 for a zero based index. */
\r
601 while( ulRxBytes > 0 )
\r
604 pxMessage->ucFifoData[ ulRxBytes ] = AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_0 ];
\r
607 /* The direction must be changed first. */
\r
608 usbCSR_SET_BIT( &ulTemp, ( AT91C_UDP_DIR ) );
\r
609 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulTemp;
\r
612 /* Must write zero's to TXCOMP, STALLSENT, RXSETUP, and the RX DATA
\r
613 registers to clear the interrupts in the CSR register. */
\r
614 usbCSR_CLEAR_BIT( &ulTemp, usbINT_CLEAR_MASK );
\r
615 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulTemp;
\r
617 /* Also clear the interrupts in the CSR1 register. */
\r
618 ulTemp = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ];
\r
619 usbCSR_CLEAR_BIT( &ulTemp, usbINT_CLEAR_MASK );
\r
620 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] = ulTemp;
\r
622 /* The message now contains the entire state and optional data from
\r
623 the USB interrupt. This can now be posted on the Rx queue ready for
\r
624 processing at the task level. */
\r
625 xTaskWokenByPost = xQueueSendFromISR( xUSBInterruptQueue, &pxMessage, xTaskWokenByPost );
\r
627 /* We may want to switch to the USB task, if this message has made
\r
628 it the highest priority task that is ready to execute. */
\r
629 portEND_SWITCHING_ISR( xTaskWokenByPost );
\r
631 /* Clear the AIC ready for the next interrupt. */
\r
632 AT91C_BASE_AIC->AIC_EOICR = 0;
\r
634 /*-----------------------------------------------------------*/
\r
636 void vUSBDemoTask( void *pvParameters )
\r
638 xISRStatus *pxMessage;
\r
640 /* The parameters are not used in this task. */
\r
641 ( void ) pvParameters;
\r
643 /* Init USB device */
\r
644 portENTER_CRITICAL();
\r
645 vInitUSBInterface();
\r
646 portEXIT_CRITICAL();
\r
648 /* Process interrupts as they arrive. The ISR takes a snapshot of the
\r
649 interrupt status then posts the information on this queue for processing
\r
650 at the task level. This simple demo implementation only processes
\r
651 a few interrupt sources. */
\r
654 if( xQueueReceive( xUSBInterruptQueue, &pxMessage, usbSHORT_DELAY ) )
\r
656 if( pxMessage->ulISR & AT91C_UDP_EPINT0 )
\r
658 /* Process end point 0 interrupt. */
\r
659 prvProcessEndPoint0Interrupt( pxMessage );
\r
662 if( pxMessage->ulISR & AT91C_UDP_ENDBUSRES )
\r
664 /* Process an end of bus reset interrupt. */
\r
665 prvResetEndPoints();
\r
670 /* The ISR did not post any data for us to process on the queue, so
\r
671 just generate and send some sample data. */
\r
672 if( eDriverState == eREADY_TO_SEND )
\r
674 prvTransmitSampleValues();
\r
679 /*-----------------------------------------------------------*/
\r
681 static void prvTransmitSampleValues( void )
\r
683 unsigned portLONG ulStatus;
\r
684 static portLONG lState = usbXUP;
\r
686 /* Variables to hold dummy x, y and z joystick axis data. */
\r
687 static signed portCHAR x = 0, y = 0, z = 0;
\r
689 /* Generate some sample data in the x and y axis - draw a square. */
\r
692 case usbXUP : x += usbDATA_INC;
\r
693 if( x >= usbMAX_COORD )
\r
699 case usbXDOWN : x -= usbDATA_INC;
\r
700 if( x <= -usbMAX_COORD )
\r
706 case usbYUP : y += usbDATA_INC;
\r
707 if( y >= usbMAX_COORD )
\r
713 case usbYDOWN : y -= usbDATA_INC;
\r
714 if( y <= -usbMAX_COORD )
\r
721 /* Just make the z axis go up and down. */
\r
724 /* Can we place data in the fifo? */
\r
725 if( !( AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] & AT91C_UDP_TXPKTRDY ) )
\r
727 /* Write our sample data to the fifo. */
\r
728 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_1 ] = x;
\r
729 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_1 ] = y;
\r
730 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_1 ] = z;
\r
732 /* Send the data. */
\r
733 portENTER_CRITICAL();
\r
735 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ];
\r
736 usbCSR_SET_BIT( &ulStatus, ( AT91C_UDP_TXPKTRDY ) );
\r
737 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] = ulStatus;
\r
739 portEXIT_CRITICAL();
\r
742 /*-----------------------------------------------------------*/
\r
744 static void prvUSBTransmitNull( void )
\r
746 unsigned portLONG ulStatus;
\r
748 /* Wait until the FIFO is free - even though we are not going to use it.
\r
749 THERE IS NO TIMEOUT HERE! */
\r
750 while( AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] & AT91C_UDP_TXPKTRDY )
\r
752 vTaskDelay( usbSHORTEST_DELAY );
\r
755 portENTER_CRITICAL();
\r
757 /* Set the length of data to send to equal the index of the next byte
\r
758 to send. This will prevent the ACK to this NULL packet causing any
\r
759 further data transmissions. */
\r
760 pxCharsForTx.ulTotalDataLength = pxCharsForTx.ulNextCharIndex;
\r
762 /* Set the TXPKTRDY bit to cause a transmission with no data. */
\r
763 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
764 usbCSR_SET_BIT( &ulStatus, ( AT91C_UDP_TXPKTRDY ) );
\r
765 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulStatus;
\r
767 portEXIT_CRITICAL();
\r
769 /*-----------------------------------------------------------*/
\r
771 static void prvSendStall( void )
\r
773 unsigned portLONG ulStatus;
\r
775 portENTER_CRITICAL();
\r
777 /* Force a stall by simply setting the FORCESTALL bit in the CSR. */
\r
778 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
779 usbCSR_SET_BIT( &ulStatus, AT91C_UDP_FORCESTALL );
\r
780 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulStatus;
\r
782 portEXIT_CRITICAL();
\r
784 /*-----------------------------------------------------------*/
\r
786 static void prvResetEndPoints( void )
\r
788 unsigned portLONG ulTemp;
\r
790 eDriverState = eJUST_RESET;
\r
792 /* Reset all the end points. */
\r
793 AT91C_BASE_UDP->UDP_RSTEP = usbEND_POINT_RESET_MASK;
\r
794 AT91C_BASE_UDP->UDP_RSTEP = ( unsigned portLONG ) 0x00;
\r
796 /* Enable data to be sent and received. */
\r
797 AT91C_BASE_UDP->UDP_FADDR = AT91C_UDP_FEN;
\r
799 /* Repair the configuration end point. */
\r
800 portENTER_CRITICAL();
\r
802 ulTemp = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
803 usbCSR_SET_BIT( &ulTemp, ( ( unsigned portLONG ) ( AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_CTRL ) ) );
\r
804 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulTemp;
\r
805 AT91F_UDP_EnableIt( AT91C_BASE_UDP, AT91C_UDP_EPINT0 );
\r
807 portEXIT_CRITICAL();
\r
809 /*-----------------------------------------------------------*/
\r
811 static void prvProcessEndPoint0Interrupt( xISRStatus *pxMessage )
\r
813 if( pxMessage->ulCSR0 & AT91C_UDP_RX_DATA_BK0 )
\r
815 /* We only expect to receive zero length data here as ACK's.
\r
816 Set the data pointer to the end of the current Tx packet to
\r
817 ensure we don't send out any more data. */
\r
818 pxCharsForTx.ulNextCharIndex = pxCharsForTx.ulTotalDataLength;
\r
821 if( pxMessage->ulCSR0 & AT91C_UDP_TXCOMP )
\r
823 /* We received a TX complete interrupt. What we do depends on
\r
824 what we sent to get this interrupt. */
\r
826 if( eDriverState == eJUST_GOT_CONFIG )
\r
828 /* We sent an acknowledgement of a SET_CONFIG request. We
\r
829 are now at the end of the enumeration. */
\r
830 AT91C_BASE_UDP->UDP_GLBSTATE = AT91C_UDP_CONFG;
\r
832 /* Read the end point for data transfer. */
\r
833 portENTER_CRITICAL();
\r
835 unsigned portLONG ulTemp;
\r
837 ulTemp = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ];
\r
838 usbCSR_SET_BIT( &ulTemp, AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_INT_IN );
\r
839 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] = ulTemp;
\r
840 AT91F_UDP_EnableIt( AT91C_BASE_UDP, AT91C_UDP_EPINT1 );
\r
842 portEXIT_CRITICAL();
\r
844 eDriverState = eREADY_TO_SEND;
\r
846 else if( eDriverState == eJUST_GOT_ADDRESS )
\r
848 /* We sent an acknowledgement of a SET_ADDRESS request. Move
\r
849 to the addressed state. */
\r
850 if( ulReceivedAddress != ( unsigned portLONG ) 0 )
\r
852 AT91C_BASE_UDP->UDP_GLBSTATE = AT91C_UDP_FADDEN;
\r
856 AT91C_BASE_UDP->UDP_GLBSTATE = 0;
\r
859 AT91C_BASE_UDP->UDP_FADDR = ( AT91C_UDP_FEN | ulReceivedAddress );
\r
860 eDriverState = eNOTHING;
\r
864 /* The TXCOMP was not for any special type of transmission. See
\r
865 if there is any more data to send. */
\r
866 prvSendNextSegment();
\r
870 if( pxMessage->ulCSR0 & AT91C_UDP_RXSETUP )
\r
872 xUSB_REQUEST xRequest;
\r
873 unsigned portCHAR ucRequest;
\r
874 unsigned portLONG ulRxBytes;
\r
876 /* A data packet is available. */
\r
877 ulRxBytes = pxMessage->ulCSR0 >> 16;
\r
878 ulRxBytes &= usbRX_COUNT_MASK;
\r
880 if( ulRxBytes >= usbEXPECTED_NUMBER_OF_BYTES )
\r
882 /* Create an xUSB_REQUEST variable from the raw bytes array. */
\r
884 xRequest.ucReqType = pxMessage->ucFifoData[ usbREQUEST_TYPE_INDEX ];
\r
885 xRequest.ucRequest = pxMessage->ucFifoData[ usbREQUEST_INDEX ];
\r
887 /* NOT PORTABLE CODE! */
\r
888 xRequest.usValue = pxMessage->ucFifoData[ usbVALUE_HIGH_BYTE ];
\r
889 xRequest.usValue <<= 8;
\r
890 xRequest.usValue |= pxMessage->ucFifoData[ usbVALUE_LOW_BYTE ];
\r
892 xRequest.usIndex = pxMessage->ucFifoData[ usbINDEX_HIGH_BYTE ];
\r
893 xRequest.usIndex <<= 8;
\r
894 xRequest.usIndex |= pxMessage->ucFifoData[ usbINDEX_LOW_BYTE ];
\r
896 xRequest.usLength = pxMessage->ucFifoData[ usbLENGTH_HIGH_BYTE ];
\r
897 xRequest.usLength <<= 8;
\r
898 xRequest.usLength |= pxMessage->ucFifoData[ usbLENGTH_LOW_BYTE ];
\r
900 /* Manipulate the ucRequestType and the ucRequest parameters to
\r
901 generate a zero based request selection. This is just done to
\r
902 break up the requests into subsections for clarity. The
\r
903 alternative would be to have more huge switch statement that would
\r
904 be difficult to optimise. */
\r
905 ucRequest = ( ( xRequest.ucReqType & 0x60 ) >> 3 );
\r
906 ucRequest |= ( xRequest.ucReqType & 0x03 );
\r
908 switch( ucRequest )
\r
910 case usbSTANDARD_DEVICE_REQUEST:
\r
911 /* Standard Device request */
\r
912 prvHandleStandardDeviceRequest( &xRequest );
\r
915 case usbSTANDARD_INTERFACE_REQUEST:
\r
916 /* Standard Interface request */
\r
917 prvHandleStandardInterfaceRequest( &xRequest );
\r
920 case usbSTANDARD_END_POINT_REQUEST:
\r
921 /* Standard Endpoint request */
\r
922 prvHandleStandardEndPointRequest( &xRequest );
\r
925 case usbCLASS_INTERFACE_REQUEST:
\r
926 /* Class Interface request */
\r
927 prvHandleClassInterfaceRequest( &xRequest );
\r
930 default: /* This is not something we want to respond to. */
\r
936 /*-----------------------------------------------------------*/
\r
938 static void prvGetStandardDeviceDescriptor( xUSB_REQUEST *pxRequest )
\r
940 /* The type is in the high byte. Return whatever has been requested. */
\r
941 switch( ( pxRequest->usValue & 0xff00 ) >> 8 )
\r
943 case usbDESCRIPTOR_TYPE_DEVICE:
\r
944 prvSendControlData( ( unsigned portCHAR * ) &pxDeviceDescriptor, pxRequest->usLength, sizeof( pxDeviceDescriptor ), pdTRUE );
\r
947 case usbDESCRIPTOR_TYPE_CONFIGURATION:
\r
948 prvSendControlData( ( unsigned portCHAR * ) &( pxConfigDescriptor ), pxRequest->usLength, sizeof( pxConfigDescriptor ), pdTRUE );
\r
951 case usbDESCRIPTOR_TYPE_STRING:
\r
953 /* The index to the string descriptor is the lower byte. */
\r
954 switch( pxRequest->usValue & 0xff )
\r
956 case usbLANGUAGE_STRING:
\r
957 prvSendControlData( ( unsigned portCHAR * ) &pxLanguageStringDescriptor, pxRequest->usLength, sizeof(pxLanguageStringDescriptor), pdTRUE );
\r
960 case usbMANUFACTURER_STRING:
\r
961 prvSendControlData( ( unsigned portCHAR * ) &pxManufacturerStringDescriptor, pxRequest->usLength, sizeof( pxManufacturerStringDescriptor ), pdTRUE );
\r
964 case usbPRODUCT_STRING:
\r
965 prvSendControlData( ( unsigned portCHAR * ) &pxProductStringDescriptor, pxRequest->usLength, sizeof( pxProductStringDescriptor ), pdTRUE );
\r
968 case usbCONFIGURATION_STRING:
\r
969 prvSendControlData( ( unsigned portCHAR * ) &pxConfigurationStringDescriptor, pxRequest->usLength, sizeof( pxConfigurationStringDescriptor ), pdTRUE );
\r
972 case usbINTERFACE_STRING:
\r
973 prvSendControlData( ( unsigned portCHAR * ) &pxInterfaceStringDescriptor, pxRequest->usLength, sizeof( pxInterfaceStringDescriptor ), pdTRUE );
\r
977 /* Don't know what this string is. */
\r
985 /* We are not responding to anything else. */
\r
990 /*-----------------------------------------------------------*/
\r
992 static void prvHandleStandardDeviceRequest( xUSB_REQUEST *pxRequest )
\r
994 unsigned portSHORT usStatus = 0;
\r
996 switch( pxRequest->ucRequest )
\r
998 case usbGET_STATUS_REQUEST:
\r
999 /* Just send two byte dummy status. */
\r
1000 prvSendControlData( ( unsigned portCHAR * ) &usStatus, sizeof( usStatus ), sizeof( usStatus ), pdFALSE );
\r
1003 case usbGET_DESCRIPTOR_REQUEST:
\r
1004 /* Send device descriptor */
\r
1005 prvGetStandardDeviceDescriptor( pxRequest );
\r
1008 case usbGET_CONFIGURATION_REQUEST:
\r
1009 /* Send selected device configuration */
\r
1010 prvSendControlData( ( unsigned portCHAR * ) &ucUSBConfig, sizeof( ucUSBConfig ), sizeof( ucUSBConfig ), pdFALSE );
\r
1013 case usbSET_FEATURE_REQUEST:
\r
1014 prvUSBTransmitNull();
\r
1017 case usbSET_ADDRESS_REQUEST:
\r
1019 /* Acknowledge the SET_ADDRESS, but (according to the manual) we
\r
1020 cannot actually move to the addressed state until we get a TXCOMP
\r
1021 interrupt from this NULL packet. Therefore we just remember the
\r
1022 address and set our state so we know we have received the address. */
\r
1023 prvUSBTransmitNull();
\r
1024 eDriverState = eJUST_GOT_ADDRESS;
\r
1025 ulReceivedAddress = ( unsigned portLONG ) pxRequest->usValue;
\r
1028 case usbSET_CONFIGURATION_REQUEST:
\r
1030 /* Acknowledge the SET_CONFIGURATION, but (according to the manual)
\r
1031 we cannot actually move to the configured state until we get a
\r
1032 TXCOMP interrupt from this NULL packet. Therefore we just remember the
\r
1033 config and set our state so we know we have received the go ahead. */
\r
1034 ucUSBConfig = ( unsigned portCHAR ) ( pxRequest->usValue & 0xff );
\r
1035 eDriverState = eJUST_GOT_CONFIG;
\r
1036 prvUSBTransmitNull();
\r
1041 /* We don't answer to anything else. */
\r
1046 /*-----------------------------------------------------------*/
\r
1048 static void prvHandleClassInterfaceRequest( xUSB_REQUEST *pxRequest )
\r
1050 switch( pxRequest->ucRequest )
\r
1052 case usbSET_IDLE_REQUEST:
\r
1053 prvUSBTransmitNull();
\r
1056 /* This minimal implementation ignores these. */
\r
1057 case usbGET_REPORT_REQUEST:
\r
1058 case usbGET_IDLE_REQUEST:
\r
1059 case usbGET_PROTOCOL_REQUEST:
\r
1060 case usbSET_REPORT_REQUEST:
\r
1061 case usbSET_PROTOCOL_REQUEST:
\r
1068 /*-----------------------------------------------------------*/
\r
1070 static void prvGetStandardInterfaceDescriptor( xUSB_REQUEST *pxRequest )
\r
1072 switch( ( pxRequest->usValue & ( unsigned portSHORT ) 0xff00 ) >> 8 )
\r
1074 case usbHID_REPORT_DESCRIPTOR:
\r
1075 prvSendControlData( ( unsigned portCHAR * ) pxReportDescriptor, pxRequest->usLength, sizeof( pxReportDescriptor ), pdTRUE );
\r
1080 /* Don't expect to send any others. */
\r
1085 /*-----------------------------------------------------------*/
\r
1087 static void prvHandleStandardInterfaceRequest( xUSB_REQUEST *pxRequest )
\r
1089 unsigned portSHORT usStatus = 0;
\r
1091 switch( pxRequest->ucRequest )
\r
1093 case usbGET_STATUS_REQUEST:
\r
1094 /* Send dummy 2 bytes. */
\r
1095 prvSendControlData( ( unsigned portCHAR * ) &usStatus, sizeof( usStatus ), sizeof( usStatus ), pdFALSE );
\r
1098 case usbGET_DESCRIPTOR_REQUEST:
\r
1099 prvGetStandardInterfaceDescriptor( pxRequest );
\r
1102 /* This minimal implementation does not respond to these. */
\r
1103 case usbGET_INTERFACE_REQUEST:
\r
1104 case usbSET_FEATURE_REQUEST:
\r
1105 case usbSET_INTERFACE_REQUEST:
\r
1112 /*-----------------------------------------------------------*/
\r
1114 static void prvHandleStandardEndPointRequest( xUSB_REQUEST *pxRequest )
\r
1116 switch( pxRequest->ucRequest )
\r
1118 /* This minimal implementation does not expect to respond to these. */
\r
1119 case usbGET_STATUS_REQUEST:
\r
1120 case usbCLEAR_FEATURE_REQUEST:
\r
1121 case usbSET_FEATURE_REQUEST:
\r
1128 /*-----------------------------------------------------------*/
\r
1130 static void vInitUSBInterface( void )
\r
1132 volatile unsigned portLONG ulTemp;
\r
1134 /* Create the queue used to communicate between the USB ISR and task. */
\r
1135 xUSBInterruptQueue = xQueueCreate( usbQUEUE_LENGTH + 1, sizeof( xISRStatus * ) );
\r
1137 /* Initialise a few state variables. */
\r
1138 pxCharsForTx.ulNextCharIndex = ( unsigned portLONG ) 0;
\r
1139 ucUSBConfig = ( unsigned portCHAR ) 0;
\r
1140 eDriverState = eNOTHING;
\r
1142 /* HARDWARE SETUP */
\r
1144 /* Set the PLL USB Divider */
\r
1145 AT91C_BASE_CKGR->CKGR_PLLR |= AT91C_CKGR_USBDIV_1;
\r
1147 /* Enables the 48MHz USB clock UDPCK and System Peripheral USB Clock. */
\r
1148 AT91C_BASE_PMC->PMC_SCER = AT91C_PMC_UDP;
\r
1149 AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_UDP);
\r
1151 /* Setup the PIO for the USB pull up resistor. */
\r
1152 AT91F_PIO_CfgOutput(AT91C_BASE_PIOA,AT91C_PIO_PA16);
\r
1154 /* Start without the pullup - this will get set at the end of this
\r
1156 AT91F_PIO_SetOutput( AT91C_BASE_PIOA, AT91C_PIO_PA16 );
\r
1158 /* When using the USB debugger the peripheral registers do not always get
\r
1159 set to the correct default values. To make sure set the relevant registers
\r
1161 AT91C_BASE_UDP->UDP_IDR = ( unsigned portLONG ) 0xffffffff;
\r
1162 AT91C_BASE_UDP->UDP_ICR = ( unsigned portLONG ) 0xffffffff;
\r
1163 AT91C_BASE_UDP->UDP_CSR[ 0 ] = ( unsigned portLONG ) 0x00;
\r
1164 AT91C_BASE_UDP->UDP_CSR[ 1 ] = ( unsigned portLONG ) 0x00;
\r
1165 AT91C_BASE_UDP->UDP_GLBSTATE = 0;
\r
1166 AT91C_BASE_UDP->UDP_FADDR = 0;
\r
1168 /* Enable the transceiver. */
\r
1169 AT91C_UDP_TRANSCEIVER_ENABLE = 0;
\r
1171 /* Enable the USB interrupts - other interrupts get enabled as the
\r
1172 enumeration process progresses. */
\r
1173 AT91F_AIC_ConfigureIt( AT91C_BASE_AIC, AT91C_ID_UDP, usbINTERRUPT_PRIORITY, AT91C_AIC_SRCTYPE_INT_LEVEL_SENSITIVE, ( void (*)( void ) ) vUSBISREntry );
\r
1174 AT91F_AIC_EnableIt( AT91C_BASE_AIC, AT91C_ID_UDP );
\r
1176 /* Wait a short while before making our presence known. */
\r
1177 vTaskDelay( usbINIT_DELAY );
\r
1178 AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, AT91C_PIO_PA16 );
\r
1180 /*-----------------------------------------------------------*/
\r
1182 static void prvSendControlData( unsigned portCHAR *pucData, unsigned portSHORT usRequestedLength, unsigned portLONG ulLengthToSend, portLONG lSendingDescriptor )
\r
1184 if( ( ( unsigned portLONG ) usRequestedLength < ulLengthToSend ) )
\r
1186 /* Cap the data length to that requested. */
\r
1187 ulLengthToSend = ( unsigned portSHORT ) usRequestedLength;
\r
1189 else if( ( ulLengthToSend < ( unsigned portLONG ) usRequestedLength ) && lSendingDescriptor )
\r
1191 /* We are sending a descriptor. If the descriptor is an exact
\r
1192 multiple of the FIFO length then it will have to be terminated
\r
1193 with a NULL packet. Set the state to indicate this if
\r
1195 if( ( ulLengthToSend % usbFIFO_LENGTH ) == 0 )
\r
1197 eDriverState = eSENDING_EVEN_DESCRIPTOR;
\r
1201 /* Here we assume that the previous message has been sent. THERE IS NO
\r
1202 BUFFER OVERFLOW PROTECTION HERE.
\r
1204 Copy the data to send into the buffer as we cannot send it all at once
\r
1205 (if it is greater than 8 bytes in length). */
\r
1206 memcpy( pxCharsForTx.ucTxBuffer, pucData, ulLengthToSend );
\r
1208 /* Reinitialise the buffer index so we start sending from the start of
\r
1210 pxCharsForTx.ulTotalDataLength = ulLengthToSend;
\r
1211 pxCharsForTx.ulNextCharIndex = ( unsigned portLONG ) 0;
\r
1213 /* Send the first 8 bytes now. The rest will get sent in response to
\r
1214 TXCOMP interrupts. */
\r
1215 prvSendNextSegment();
\r
1217 /*-----------------------------------------------------------*/
\r
1219 static void prvSendNextSegment( void )
\r
1221 volatile unsigned portLONG ulNextLength, ulStatus, ulLengthLeftToSend;
\r
1223 /* Is there any data to send? */
\r
1224 if( pxCharsForTx.ulTotalDataLength > pxCharsForTx.ulNextCharIndex )
\r
1226 ulLengthLeftToSend = pxCharsForTx.ulTotalDataLength - pxCharsForTx.ulNextCharIndex;
\r
1228 /* We can only send 8 bytes to the fifo at a time. */
\r
1229 if( ulLengthLeftToSend > usbFIFO_LENGTH )
\r
1231 ulNextLength = usbFIFO_LENGTH;
\r
1235 ulNextLength = ulLengthLeftToSend;
\r
1238 /* Wait until we can place data in the fifo. THERE IS NO TIMEOUT
\r
1240 while( AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] & AT91C_UDP_TXPKTRDY )
\r
1242 vTaskDelay( usbSHORTEST_DELAY );
\r
1245 /* Write the data to the FIFO. */
\r
1246 while( ulNextLength > ( unsigned portLONG ) 0 )
\r
1248 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_0 ] = pxCharsForTx.ucTxBuffer[ pxCharsForTx.ulNextCharIndex ];
\r
1251 pxCharsForTx.ulNextCharIndex++;
\r
1254 /* Start the transmission. */
\r
1255 portENTER_CRITICAL();
\r
1257 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
1258 usbCSR_SET_BIT( &ulStatus, ( ( unsigned portLONG ) 0x10 ) );
\r
1259 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulStatus;
\r
1261 portEXIT_CRITICAL();
\r
1265 /* There is no data to send. If we were sending a descriptor and the
\r
1266 descriptor was an exact multiple of the max packet size then we need
\r
1267 to send a null to terminate the transmission. */
\r
1268 if( eDriverState == eSENDING_EVEN_DESCRIPTOR )
\r
1270 prvUSBTransmitNull();
\r
1271 eDriverState = eNOTHING;
\r