2 FreeRTOS.org V4.7.1 - Copyright (C) 2003-2008 Richard Barry.
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4 This file is part of the FreeRTOS.org distribution.
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6 FreeRTOS.org is free software; you can redistribute it and/or modify
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7 it under the terms of the GNU General Public License as published by
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8 the Free Software Foundation; either version 2 of the License, or
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9 (at your option) any later version.
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11 FreeRTOS.org is distributed in the hope that it will be useful,
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12 but WITHOUT ANY WARRANTY; without even the implied warranty of
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13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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14 GNU General Public License for more details.
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16 You should have received a copy of the GNU General Public License
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17 along with FreeRTOS.org; if not, write to the Free Software
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18 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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20 A special exception to the GPL can be applied should you wish to distribute
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21 a combined work that includes FreeRTOS.org, without being obliged to provide
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22 the source code for any proprietary components. See the licensing section
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23 of http://www.FreeRTOS.org for full details of how and when the exception
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26 ***************************************************************************
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28 Please ensure to read the configuration and relevant port sections of the
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29 online documentation.
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31 +++ http://www.FreeRTOS.org +++
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32 Documentation, latest information, license and contact details.
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34 +++ http://www.SafeRTOS.com +++
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35 A version that is certified for use in safety critical systems.
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37 +++ http://www.OpenRTOS.com +++
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38 Commercial support, development, porting, licensing and training services.
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40 ***************************************************************************
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44 Sample interrupt driven USB device driver. This is a minimal implementation
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45 for demonstration only. Although functional, it is not a full and compliant
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48 The USB device enumerates as a simple 3 axis joystick, and once configured
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49 transmits 3 axis of data which can be viewed from the USB host machine.
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51 This file implements the USB interrupt service routine, and a demo FreeRTOS
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52 task. The interrupt service routine handles the USB hardware - taking a
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53 snapshot of the USB status at the point of the interrupt. The task receives
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54 the status information from the interrupt for processing at the task level.
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56 See the FreeRTOS.org WEB documentation for more information.
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62 + Descriptors that have a length that is an exact multiple of usbFIFO_LENGTH
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63 can now be transmitted. To this end an extra parameter has been
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64 added to the prvSendControlData() function, and the state
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65 eSENDING_EVEN_DESCRIPTOR has been introduced. Thanks to Scott Miller for
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66 assisting with this contribution.
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70 + Replaced the duplicated RX_DATA_BK0 in the interrupt mask with the
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74 /* Standard includes. */
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77 /* Demo board includes. */
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80 /* Scheduler includes. */
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81 #include "FreeRTOS.h"
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86 /* Descriptor type definitions. */
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87 #define usbDESCRIPTOR_TYPE_DEVICE ( 0x01 )
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88 #define usbDESCRIPTOR_TYPE_CONFIGURATION ( 0x02 )
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89 #define usbDESCRIPTOR_TYPE_STRING ( 0x03 )
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91 /* USB request type definitions. */
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92 #define usbGET_REPORT_REQUEST ( 0x01 )
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93 #define usbGET_IDLE_REQUEST ( 0x02 )
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94 #define usbGET_PROTOCOL_REQUEST ( 0x03 )
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95 #define usbSET_REPORT_REQUEST ( 0x09 )
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96 #define usbSET_IDLE_REQUEST ( 0x0A )
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97 #define usbSET_PROTOCOL_REQUEST ( 0x0B )
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98 #define usbGET_CONFIGURATION_REQUEST ( 0x08 )
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99 #define usbGET_STATUS_REQUEST ( 0x00 )
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100 #define usbCLEAR_FEATURE_REQUEST ( 0x01 )
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101 #define usbSET_FEATURE_REQUEST ( 0x03 )
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102 #define usbSET_ADDRESS_REQUEST ( 0x05 )
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103 #define usbGET_DESCRIPTOR_REQUEST ( 0x06 )
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104 #define usbSET_CONFIGURATION_REQUEST ( 0x09 )
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105 #define usbGET_INTERFACE_REQUEST ( 0x0A )
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106 #define usbSET_INTERFACE_REQUEST ( 0x0B )
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109 /* Misc USB definitions. */
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110 #define usbDEVICE_CLASS_VENDOR_SPECIFIC ( 0xFF )
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111 #define usbBUS_POWERED ( 0x80 )
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112 #define usbHID_REPORT_DESCRIPTOR ( 0x22 )
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113 #define AT91C_UDP_TRANSCEIVER_ENABLE ( *( ( unsigned long * ) 0xfffb0074 ) )
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115 /* Index to the various string. */
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116 #define usbLANGUAGE_STRING ( 0 )
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117 #define usbMANUFACTURER_STRING ( 1 )
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118 #define usbPRODUCT_STRING ( 2 )
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119 #define usbCONFIGURATION_STRING ( 3 )
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120 #define usbINTERFACE_STRING ( 4 )
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122 /* Data indexes for reading the request from the xISRStatus.ucFifoData[]
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123 into xUSB_REQUEST. The data order is designed for speed - so looks a
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125 #define usbREQUEST_TYPE_INDEX ( 7 )
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126 #define usbREQUEST_INDEX ( 6 )
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127 #define usbVALUE_HIGH_BYTE ( 4 )
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128 #define usbVALUE_LOW_BYTE ( 5 )
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129 #define usbINDEX_HIGH_BYTE ( 2 )
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130 #define usbINDEX_LOW_BYTE ( 3 )
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131 #define usbLENGTH_HIGH_BYTE ( 0 )
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132 #define usbLENGTH_LOW_BYTE ( 1 )
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134 /* Misc application definitions. */
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135 #define usbINTERRUPT_PRIORITY ( 3 )
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136 #define usbQUEUE_LENGTH ( 0x3 ) /* Must have all bits set! */
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137 #define usbFIFO_LENGTH ( ( unsigned portLONG ) 8 )
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138 #define usbEND_POINT_0 ( 0 )
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139 #define usbEND_POINT_1 ( 1 )
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140 #define usbXUP ( 1 )
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141 #define usbXDOWN ( 2 )
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142 #define usbYUP ( 3 )
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143 #define usbYDOWN ( 4 )
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144 #define usbMAX_COORD ( 120 )
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145 #define usbMAX_TX_MESSAGE_SIZE ( 128 )
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146 #define usbRX_COUNT_MASK ( ( unsigned portLONG ) 0x7ff )
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147 #define AT91C_UDP_STALLSENT AT91C_UDP_ISOERROR
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148 #define usbSHORTEST_DELAY ( ( portTickType ) 1 )
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149 #define usbINIT_DELAY ( ( portTickType ) 500 / portTICK_RATE_MS )
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150 #define usbSHORT_DELAY ( ( portTickType ) 50 / portTICK_RATE_MS )
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151 #define usbEND_POINT_RESET_MASK ( ( unsigned portLONG ) 0x0f )
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152 #define usbDATA_INC ( ( portCHAR ) 5 )
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153 #define usbEXPECTED_NUMBER_OF_BYTES ( ( unsigned portLONG ) 8 )
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155 /* Control request types. */
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156 #define usbSTANDARD_DEVICE_REQUEST ( 0 )
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157 #define usbSTANDARD_INTERFACE_REQUEST ( 1 )
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158 #define usbSTANDARD_END_POINT_REQUEST ( 2 )
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159 #define usbCLASS_INTERFACE_REQUEST ( 5 )
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161 /*-----------------------------------------------------------*/
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163 /* Structure used to take a snapshot of the USB status from within the ISR. */
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164 typedef struct X_ISR_STATUS
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166 unsigned portLONG ulISR;
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167 unsigned portLONG ulCSR0;
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168 unsigned portCHAR ucFifoData[ 8 ];
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171 /* Structure used to hold the received requests. */
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174 unsigned portCHAR ucReqType;
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175 unsigned portCHAR ucRequest;
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176 unsigned portSHORT usValue;
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177 unsigned portSHORT usIndex;
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178 unsigned portSHORT usLength;
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187 eSENDING_EVEN_DESCRIPTOR,
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191 /* Structure used to control the data being sent to the host. */
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194 unsigned portCHAR ucTxBuffer[ usbMAX_TX_MESSAGE_SIZE ];
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195 unsigned portLONG ulNextCharIndex;
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196 unsigned portLONG ulTotalDataLength;
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199 /*-----------------------------------------------------------*/
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202 * The USB interrupt service routine. This takes a snapshot of the USB
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203 * device at the time of the interrupt, clears the interrupts, and posts
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204 * the data to the USB processing task.
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206 __arm void vUSB_ISR( void );
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209 * Called after the bus reset interrupt - this function readies all the
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210 * end points for communication.
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212 static void prvResetEndPoints( void );
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215 * Setup the USB hardware, install the interrupt service routine and
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216 * initialise all the state variables.
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218 static void vInitUSBInterface( void );
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221 * Decode and act upon an interrupt generated by the control end point.
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223 static void prvProcessEndPoint0Interrupt( xISRStatus *pxMessage );
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226 * For simplicity requests are separated into device, interface, class
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227 * interface and end point requests.
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229 * Decode and handle standard device requests originating on the control
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232 static void prvHandleStandardDeviceRequest( xUSB_REQUEST *pxRequest );
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235 * For simplicity requests are separated into device, interface, class
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236 * interface and end point requests.
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238 * Decode and handle standard interface requests originating on the control
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241 static void prvHandleStandardInterfaceRequest( xUSB_REQUEST *pxRequest );
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244 * For simplicity requests are separated into device, interface, class
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245 * interface and end point requests.
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247 * Decode and handle standard end point requests originating on the control
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250 static void prvHandleStandardEndPointRequest( xUSB_REQUEST *pxRequest );
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253 * For simplicity requests are separated into device, interface, class
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254 * interface and end point requests.
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256 * Decode and handle the class interface requests.
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258 static void prvHandleClassInterfaceRequest( xUSB_REQUEST *pxRequest );
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261 * Setup the Tx buffer to send data in response to a control request.
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263 * The data to be transmitted is buffered, the state variables are updated,
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264 * then prvSendNextSegment() is called to start the transmission off. Once
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265 * the first segment has been sent the remaining segments are transmitted
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266 * in response to TXCOMP interrupts until the entire buffer has been
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269 static void prvSendControlData( unsigned portCHAR *pucData, unsigned portSHORT usRequestedLength, unsigned portLONG ulLengthLeftToSend, portLONG lSendingDescriptor );
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272 * Examine the Tx buffer to see if there is any more data to be transmitted.
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274 * If there is data to be transmitted then send the next segment. A segment
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275 * can have a maximum of 8 bytes (this is defined as the maximum for the end
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276 * point by the descriptor). The final segment may be less than 8 bytes if
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277 * the total data length was not an exact multiple of 8.
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279 static void prvSendNextSegment( void );
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282 * A stall condition is forced each time the host makes a request that is not
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283 * supported by this minimal implementation.
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285 * A stall is forced by setting the appropriate bit in the end points control
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286 * and status register.
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288 static void prvSendStall( void );
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291 * A NULL (or zero length packet) is transmitted in acknowledge the reception
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292 * of certain events from the host.
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294 static void prvUSBTransmitNull( void );
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297 * When the host requests a descriptor this function is called to determine
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298 * which descriptor is being requested and start its transmission.
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300 static void prvGetStandardInterfaceDescriptor( xUSB_REQUEST *pxRequest );
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303 * This demo USB device enumerates as a simple 3 axis joystick. Once
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304 * configured this function is periodically called to generate some sample
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307 * The x and y axis are made to move in a square. The z axis is made to
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308 * repeatedly increment up to its maximum.
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310 static void prvTransmitSampleValues( void );
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313 * The created task to handle the USB demo functionality.
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315 void vUSBDemoTask( void *pvParameters );
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317 /*-----------------------------------------------------------*/
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320 - DESCRIPTOR DEFINITIONS -
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323 /* String descriptors used during the enumeration process.
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324 These take the form:
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327 Length of descriptor,
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332 const portCHAR pxLanguageStringDescriptor[] =
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335 usbDESCRIPTOR_TYPE_STRING,
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339 const portCHAR pxManufacturerStringDescriptor[] =
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342 usbDESCRIPTOR_TYPE_STRING,
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354 const portCHAR pxProductStringDescriptor[] =
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357 usbDESCRIPTOR_TYPE_STRING,
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382 const portCHAR pxConfigurationStringDescriptor[] =
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385 usbDESCRIPTOR_TYPE_STRING,
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407 const portCHAR pxInterfaceStringDescriptor[] =
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410 usbDESCRIPTOR_TYPE_STRING,
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428 /* Enumeration descriptors. */
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429 const portCHAR pxReportDescriptor[] =
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431 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */
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432 0x09, 0x04, /* USAGE (Joystick) */
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433 0xa1, 0x01, /* COLLECTION (Application) */
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434 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */
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435 0x09, 0x01, /* USAGE (Pointer) */
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436 0xa1, 0x00, /* COLLECTION (Physical) */
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437 0x09, 0x30, /* USAGE (X) */
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438 0x09, 0x31, /* USAGE (Y) */
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439 0x09, 0x32, /* USAGE (Z) */
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440 0x15, 0x81, /* LOGICAL_MINIMUM (-127) */
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441 0x25, 0x7f, /* LOGICAL_MAXIMUM (127) */
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442 0x75, 0x08, /* REPORT_SIZE (8) */
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443 0x95, 0x03, /* REPORT_COUNT (3) */
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444 0x81, 0x02, /* INPUT (Data,Var,Abs) */
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445 0xc0, /* END_COLLECTION */
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446 0xc0 /* END_COLLECTION */
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449 const char pxDeviceDescriptor[] =
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451 /* Device descriptor */
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452 0x12, /* bLength */
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453 0x01, /* bDescriptorType */
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454 0x10, 0x01, /* bcdUSBL */
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455 usbDEVICE_CLASS_VENDOR_SPECIFIC, /* bDeviceClass: */
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456 0x00, /* bDeviceSubclass: */
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457 0x00, /* bDeviceProtocol: */
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458 0x08, /* bMaxPacketSize0 */
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459 0xFF, 0xFF, /* idVendorL */
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460 0x01, 0x00, /* idProductL */
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461 0x00, 0x01, /* bcdDeviceL */
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462 usbMANUFACTURER_STRING, /* iManufacturer */
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463 usbPRODUCT_STRING, /* iProduct */
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464 0x00, /* SerialNumber */
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465 0x01 /* bNumConfigs */
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468 const char pxConfigDescriptor[] = {
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469 /* Configuration 1 descriptor */
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470 0x09, /* CbLength */
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471 0x02, /* CbDescriptorType */
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472 0x22, 0x00, /* CwTotalLength 2 EP + Control */
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473 0x01, /* CbNumInterfaces */
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474 0x01, /* CbConfigurationValue */
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475 usbCONFIGURATION_STRING,/* CiConfiguration */
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476 usbBUS_POWERED, /* CbmAttributes Bus powered + Remote Wakeup*/
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477 0x32, /* CMaxPower: 100mA */
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479 /* Joystick Interface Descriptor Requirement */
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480 0x09, /* bLength */
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481 0x04, /* bDescriptorType */
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482 0x00, /* bInterfaceNumber */
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483 0x00, /* bAlternateSetting */
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484 0x01, /* bNumEndpoints */
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485 0x03, /* bInterfaceClass: HID code */
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486 0x00, /* bInterfaceSubclass */
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487 0x00, /* bInterfaceProtocol */
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488 usbINTERFACE_STRING,/* iInterface */
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490 /* HID Descriptor */
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491 0x09, /* bLength */
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492 0x21, /* bDescriptor type: HID Descriptor Type */
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493 0x00, 0x01, /* bcdHID */
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494 0x00, /* bCountryCode */
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495 0x01, /* bNumDescriptors */
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496 usbHID_REPORT_DESCRIPTOR, /* bDescriptorType */
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497 sizeof( pxReportDescriptor ), 0x00, /* wItemLength */
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499 /* Endpoint 1 descriptor */
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500 0x07, /* bLength */
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501 0x05, /* bDescriptorType */
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502 0x81, /* bEndpointAddress, Endpoint 01 - IN */
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503 0x03, /* bmAttributes INT */
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504 0x03, 0x00, /* wMaxPacketSize: 3 bytes (x, y, z) */
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505 0x0A /* bInterval */
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508 /*-----------------------------------------------------------*/
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510 /* File scope state variables. */
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511 static unsigned portCHAR ucUSBConfig = ( unsigned portCHAR ) 0;
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512 static unsigned portLONG ulReceivedAddress = ( unsigned portLONG ) 0;
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513 static eDRIVER_STATE eDriverState = eNOTHING;
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515 /* Array in which the USB interrupt status is passed between the ISR and task. */
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516 static xISRStatus xISRMessages[ usbQUEUE_LENGTH + 1 ];
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518 /* Structure used to control the characters being sent to the host. */
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519 static xTX_MESSAGE pxCharsForTx;
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521 /* Queue used to pass messages between the ISR and the task. */
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522 static xQueueHandle xUSBInterruptQueue;
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524 /* ISR entry has to be written in the asm file as we want a context switch
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525 to occur from within the ISR. See the port documentation on the FreeRTOS.org
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526 WEB site for more information. */
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527 extern void vUSBISREntry( void );
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529 /*-----------------------------------------------------------*/
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531 /* Macros to manipulate the control and status registers. These registers
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532 cannot be accessed using a direct read modify write operation outside of the
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533 ISR as some bits are left unchanged by writing with a 0, and some are left
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534 unchanged by writing with a 1. */
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536 #define usbINT_CLEAR_MASK (AT91C_UDP_TXCOMP | AT91C_UDP_STALLSENT | AT91C_UDP_RXSETUP | AT91C_UDP_RX_DATA_BK0 | AT91C_UDP_RX_DATA_BK1 )
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538 #define usbCSR_SET_BIT( pulValueNow, ulBit ) \
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540 /* Set TXCOMP, RX_DATA_BK0, RXSETUP, */ \
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541 /* STALLSENT and RX_DATA_BK1 to 1 so the */ \
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542 /* write has no effect. */ \
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543 ( * ( ( unsigned portLONG * ) pulValueNow ) ) |= ( unsigned portLONG ) 0x4f; \
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545 /* Clear the FORCE_STALL and TXPKTRDY bits */ \
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546 /* so the write has no effect. */ \
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547 ( * ( ( unsigned portLONG * ) pulValueNow ) ) &= ( unsigned portLONG ) 0xffffffcf; \
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549 /* Set whichever bit we want set. */ \
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550 ( * ( ( unsigned portLONG * ) pulValueNow ) ) |= ( ulBit ); \
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553 #define usbCSR_CLEAR_BIT( pulValueNow, ulBit ) \
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555 /* Set TXCOMP, RX_DATA_BK0, RXSETUP, */ \
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556 /* STALLSENT and RX_DATA_BK1 to 1 so the */ \
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557 /* write has no effect. */ \
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558 ( * ( ( unsigned portLONG * ) pulValueNow ) ) |= ( unsigned portLONG ) 0x4f; \
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560 /* Clear the FORCE_STALL and TXPKTRDY bits */ \
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561 /* so the write has no effect. */ \
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562 ( * ( ( unsigned portLONG * ) pulValueNow ) ) &= ( unsigned portLONG ) 0xffffffcf; \
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564 /* Clear whichever bit we want clear. */ \
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565 ( * ( ( unsigned portLONG * ) pulValueNow ) ) &= ( ~ulBit ); \
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568 /*-----------------------------------------------------------*/
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570 __arm void vUSB_ISR( void )
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572 portBASE_TYPE xTaskWokenByPost = pdFALSE;
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573 static volatile unsigned portLONG ulNextMessage = 0;
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574 xISRStatus *pxMessage;
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575 unsigned portLONG ulTemp, ulRxBytes;
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577 /* Take the next message from the queue. Note that usbQUEUE_LENGTH *must*
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578 be all 1's, as in 0x01, 0x03, 0x07, etc. */
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579 pxMessage = &( xISRMessages[ ( ulNextMessage & usbQUEUE_LENGTH ) ] );
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582 /* Take a snapshot of the current USB state for processing at the task
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584 pxMessage->ulISR = AT91C_BASE_UDP->UDP_ISR;
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585 pxMessage->ulCSR0 = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
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587 /* Clear the interrupts from the ICR register. The bus end interrupt is
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588 cleared separately as it does not appear in the mask register. */
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589 AT91C_BASE_UDP->UDP_ICR = AT91C_BASE_UDP->UDP_IMR | AT91C_UDP_ENDBUSRES;
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591 /* If there are bytes in the FIFO then we have to retrieve them here.
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592 Ideally this would be done at the task level. However we need to clear the
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593 RXSETUP interrupt before leaving the ISR, and this may cause the data in
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594 the FIFO to be overwritten. Also the DIR bit has to be changed before the
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595 RXSETUP bit is cleared (as per the SAM7 manual). */
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596 ulTemp = pxMessage->ulCSR0;
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598 /* Are there any bytes in the FIFO? */
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599 ulRxBytes = ulTemp >> 16;
\r
600 ulRxBytes &= usbRX_COUNT_MASK;
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602 /* With this minimal implementation we are only interested in receiving
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603 setup bytes on the control end point. */
\r
604 if( ( ulRxBytes > 0 ) && ( ulTemp & AT91C_UDP_RXSETUP ) )
\r
606 /* Take off 1 for a zero based index. */
\r
607 while( ulRxBytes > 0 )
\r
610 pxMessage->ucFifoData[ ulRxBytes ] = AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_0 ];
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613 /* The direction must be changed first. */
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614 usbCSR_SET_BIT( &ulTemp, ( AT91C_UDP_DIR ) );
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615 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulTemp;
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618 /* Must write zero's to TXCOMP, STALLSENT, RXSETUP, and the RX DATA
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619 registers to clear the interrupts in the CSR register. */
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620 usbCSR_CLEAR_BIT( &ulTemp, usbINT_CLEAR_MASK );
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621 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulTemp;
\r
623 /* Also clear the interrupts in the CSR1 register. */
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624 ulTemp = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ];
\r
625 usbCSR_CLEAR_BIT( &ulTemp, usbINT_CLEAR_MASK );
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626 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] = ulTemp;
\r
628 /* The message now contains the entire state and optional data from
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629 the USB interrupt. This can now be posted on the Rx queue ready for
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630 processing at the task level. */
\r
631 xTaskWokenByPost = xQueueSendFromISR( xUSBInterruptQueue, &pxMessage, xTaskWokenByPost );
\r
633 /* We may want to switch to the USB task, if this message has made
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634 it the highest priority task that is ready to execute. */
\r
635 portEND_SWITCHING_ISR( xTaskWokenByPost );
\r
637 /* Clear the AIC ready for the next interrupt. */
\r
638 AT91C_BASE_AIC->AIC_EOICR = 0;
\r
640 /*-----------------------------------------------------------*/
\r
642 void vUSBDemoTask( void *pvParameters )
\r
644 xISRStatus *pxMessage;
\r
646 /* The parameters are not used in this task. */
\r
647 ( void ) pvParameters;
\r
649 /* Init USB device */
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650 portENTER_CRITICAL();
\r
651 vInitUSBInterface();
\r
652 portEXIT_CRITICAL();
\r
654 /* Process interrupts as they arrive. The ISR takes a snapshot of the
\r
655 interrupt status then posts the information on this queue for processing
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656 at the task level. This simple demo implementation only processes
\r
657 a few interrupt sources. */
\r
660 if( xQueueReceive( xUSBInterruptQueue, &pxMessage, usbSHORT_DELAY ) )
\r
662 if( pxMessage->ulISR & AT91C_UDP_EPINT0 )
\r
664 /* Process end point 0 interrupt. */
\r
665 prvProcessEndPoint0Interrupt( pxMessage );
\r
668 if( pxMessage->ulISR & AT91C_UDP_ENDBUSRES )
\r
670 /* Process an end of bus reset interrupt. */
\r
671 prvResetEndPoints();
\r
676 /* The ISR did not post any data for us to process on the queue, so
\r
677 just generate and send some sample data. */
\r
678 if( eDriverState == eREADY_TO_SEND )
\r
680 prvTransmitSampleValues();
\r
685 /*-----------------------------------------------------------*/
\r
687 static void prvTransmitSampleValues( void )
\r
689 unsigned portLONG ulStatus;
\r
690 static portLONG lState = usbXUP;
\r
692 /* Variables to hold dummy x, y and z joystick axis data. */
\r
693 static signed portCHAR x = 0, y = 0, z = 0;
\r
695 /* Generate some sample data in the x and y axis - draw a square. */
\r
698 case usbXUP : x += usbDATA_INC;
\r
699 if( x >= usbMAX_COORD )
\r
705 case usbXDOWN : x -= usbDATA_INC;
\r
706 if( x <= -usbMAX_COORD )
\r
712 case usbYUP : y += usbDATA_INC;
\r
713 if( y >= usbMAX_COORD )
\r
719 case usbYDOWN : y -= usbDATA_INC;
\r
720 if( y <= -usbMAX_COORD )
\r
727 /* Just make the z axis go up and down. */
\r
730 /* Can we place data in the fifo? */
\r
731 if( !( AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] & AT91C_UDP_TXPKTRDY ) )
\r
733 /* Write our sample data to the fifo. */
\r
734 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_1 ] = x;
\r
735 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_1 ] = y;
\r
736 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_1 ] = z;
\r
738 /* Send the data. */
\r
739 portENTER_CRITICAL();
\r
741 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ];
\r
742 usbCSR_SET_BIT( &ulStatus, ( AT91C_UDP_TXPKTRDY ) );
\r
743 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] = ulStatus;
\r
745 portEXIT_CRITICAL();
\r
748 /*-----------------------------------------------------------*/
\r
750 static void prvUSBTransmitNull( void )
\r
752 unsigned portLONG ulStatus;
\r
754 /* Wait until the FIFO is free - even though we are not going to use it.
\r
755 THERE IS NO TIMEOUT HERE! */
\r
756 while( AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] & AT91C_UDP_TXPKTRDY )
\r
758 vTaskDelay( usbSHORTEST_DELAY );
\r
761 portENTER_CRITICAL();
\r
763 /* Set the length of data to send to equal the index of the next byte
\r
764 to send. This will prevent the ACK to this NULL packet causing any
\r
765 further data transmissions. */
\r
766 pxCharsForTx.ulTotalDataLength = pxCharsForTx.ulNextCharIndex;
\r
768 /* Set the TXPKTRDY bit to cause a transmission with no data. */
\r
769 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
770 usbCSR_SET_BIT( &ulStatus, ( AT91C_UDP_TXPKTRDY ) );
\r
771 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulStatus;
\r
773 portEXIT_CRITICAL();
\r
775 /*-----------------------------------------------------------*/
\r
777 static void prvSendStall( void )
\r
779 unsigned portLONG ulStatus;
\r
781 portENTER_CRITICAL();
\r
783 /* Force a stall by simply setting the FORCESTALL bit in the CSR. */
\r
784 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
785 usbCSR_SET_BIT( &ulStatus, AT91C_UDP_FORCESTALL );
\r
786 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulStatus;
\r
788 portEXIT_CRITICAL();
\r
790 /*-----------------------------------------------------------*/
\r
792 static void prvResetEndPoints( void )
\r
794 unsigned portLONG ulTemp;
\r
796 eDriverState = eJUST_RESET;
\r
798 /* Reset all the end points. */
\r
799 AT91C_BASE_UDP->UDP_RSTEP = usbEND_POINT_RESET_MASK;
\r
800 AT91C_BASE_UDP->UDP_RSTEP = ( unsigned portLONG ) 0x00;
\r
802 /* Enable data to be sent and received. */
\r
803 AT91C_BASE_UDP->UDP_FADDR = AT91C_UDP_FEN;
\r
805 /* Repair the configuration end point. */
\r
806 portENTER_CRITICAL();
\r
808 ulTemp = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
809 usbCSR_SET_BIT( &ulTemp, ( ( unsigned portLONG ) ( AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_CTRL ) ) );
\r
810 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulTemp;
\r
811 AT91F_UDP_EnableIt( AT91C_BASE_UDP, AT91C_UDP_EPINT0 );
\r
813 portEXIT_CRITICAL();
\r
815 /*-----------------------------------------------------------*/
\r
817 static void prvProcessEndPoint0Interrupt( xISRStatus *pxMessage )
\r
819 if( pxMessage->ulCSR0 & AT91C_UDP_RX_DATA_BK0 )
\r
821 /* We only expect to receive zero length data here as ACK's.
\r
822 Set the data pointer to the end of the current Tx packet to
\r
823 ensure we don't send out any more data. */
\r
824 pxCharsForTx.ulNextCharIndex = pxCharsForTx.ulTotalDataLength;
\r
827 if( pxMessage->ulCSR0 & AT91C_UDP_TXCOMP )
\r
829 /* We received a TX complete interrupt. What we do depends on
\r
830 what we sent to get this interrupt. */
\r
832 if( eDriverState == eJUST_GOT_CONFIG )
\r
834 /* We sent an acknowledgement of a SET_CONFIG request. We
\r
835 are now at the end of the enumeration. */
\r
836 AT91C_BASE_UDP->UDP_GLBSTATE = AT91C_UDP_CONFG;
\r
838 /* Read the end point for data transfer. */
\r
839 portENTER_CRITICAL();
\r
841 unsigned portLONG ulTemp;
\r
843 ulTemp = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ];
\r
844 usbCSR_SET_BIT( &ulTemp, AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_INT_IN );
\r
845 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] = ulTemp;
\r
846 AT91F_UDP_EnableIt( AT91C_BASE_UDP, AT91C_UDP_EPINT1 );
\r
848 portEXIT_CRITICAL();
\r
850 eDriverState = eREADY_TO_SEND;
\r
852 else if( eDriverState == eJUST_GOT_ADDRESS )
\r
854 /* We sent an acknowledgement of a SET_ADDRESS request. Move
\r
855 to the addressed state. */
\r
856 if( ulReceivedAddress != ( unsigned portLONG ) 0 )
\r
858 AT91C_BASE_UDP->UDP_GLBSTATE = AT91C_UDP_FADDEN;
\r
862 AT91C_BASE_UDP->UDP_GLBSTATE = 0;
\r
865 AT91C_BASE_UDP->UDP_FADDR = ( AT91C_UDP_FEN | ulReceivedAddress );
\r
866 eDriverState = eNOTHING;
\r
870 /* The TXCOMP was not for any special type of transmission. See
\r
871 if there is any more data to send. */
\r
872 prvSendNextSegment();
\r
876 if( pxMessage->ulCSR0 & AT91C_UDP_RXSETUP )
\r
878 xUSB_REQUEST xRequest;
\r
879 unsigned portCHAR ucRequest;
\r
880 unsigned portLONG ulRxBytes;
\r
882 /* A data packet is available. */
\r
883 ulRxBytes = pxMessage->ulCSR0 >> 16;
\r
884 ulRxBytes &= usbRX_COUNT_MASK;
\r
886 if( ulRxBytes >= usbEXPECTED_NUMBER_OF_BYTES )
\r
888 /* Create an xUSB_REQUEST variable from the raw bytes array. */
\r
890 xRequest.ucReqType = pxMessage->ucFifoData[ usbREQUEST_TYPE_INDEX ];
\r
891 xRequest.ucRequest = pxMessage->ucFifoData[ usbREQUEST_INDEX ];
\r
893 /* NOT PORTABLE CODE! */
\r
894 xRequest.usValue = pxMessage->ucFifoData[ usbVALUE_HIGH_BYTE ];
\r
895 xRequest.usValue <<= 8;
\r
896 xRequest.usValue |= pxMessage->ucFifoData[ usbVALUE_LOW_BYTE ];
\r
898 xRequest.usIndex = pxMessage->ucFifoData[ usbINDEX_HIGH_BYTE ];
\r
899 xRequest.usIndex <<= 8;
\r
900 xRequest.usIndex |= pxMessage->ucFifoData[ usbINDEX_LOW_BYTE ];
\r
902 xRequest.usLength = pxMessage->ucFifoData[ usbLENGTH_HIGH_BYTE ];
\r
903 xRequest.usLength <<= 8;
\r
904 xRequest.usLength |= pxMessage->ucFifoData[ usbLENGTH_LOW_BYTE ];
\r
906 /* Manipulate the ucRequestType and the ucRequest parameters to
\r
907 generate a zero based request selection. This is just done to
\r
908 break up the requests into subsections for clarity. The
\r
909 alternative would be to have more huge switch statement that would
\r
910 be difficult to optimise. */
\r
911 ucRequest = ( ( xRequest.ucReqType & 0x60 ) >> 3 );
\r
912 ucRequest |= ( xRequest.ucReqType & 0x03 );
\r
914 switch( ucRequest )
\r
916 case usbSTANDARD_DEVICE_REQUEST:
\r
917 /* Standard Device request */
\r
918 prvHandleStandardDeviceRequest( &xRequest );
\r
921 case usbSTANDARD_INTERFACE_REQUEST:
\r
922 /* Standard Interface request */
\r
923 prvHandleStandardInterfaceRequest( &xRequest );
\r
926 case usbSTANDARD_END_POINT_REQUEST:
\r
927 /* Standard Endpoint request */
\r
928 prvHandleStandardEndPointRequest( &xRequest );
\r
931 case usbCLASS_INTERFACE_REQUEST:
\r
932 /* Class Interface request */
\r
933 prvHandleClassInterfaceRequest( &xRequest );
\r
936 default: /* This is not something we want to respond to. */
\r
942 /*-----------------------------------------------------------*/
\r
944 static void prvGetStandardDeviceDescriptor( xUSB_REQUEST *pxRequest )
\r
946 /* The type is in the high byte. Return whatever has been requested. */
\r
947 switch( ( pxRequest->usValue & 0xff00 ) >> 8 )
\r
949 case usbDESCRIPTOR_TYPE_DEVICE:
\r
950 prvSendControlData( ( unsigned portCHAR * ) &pxDeviceDescriptor, pxRequest->usLength, sizeof( pxDeviceDescriptor ), pdTRUE );
\r
953 case usbDESCRIPTOR_TYPE_CONFIGURATION:
\r
954 prvSendControlData( ( unsigned portCHAR * ) &( pxConfigDescriptor ), pxRequest->usLength, sizeof( pxConfigDescriptor ), pdTRUE );
\r
957 case usbDESCRIPTOR_TYPE_STRING:
\r
959 /* The index to the string descriptor is the lower byte. */
\r
960 switch( pxRequest->usValue & 0xff )
\r
962 case usbLANGUAGE_STRING:
\r
963 prvSendControlData( ( unsigned portCHAR * ) &pxLanguageStringDescriptor, pxRequest->usLength, sizeof(pxLanguageStringDescriptor), pdTRUE );
\r
966 case usbMANUFACTURER_STRING:
\r
967 prvSendControlData( ( unsigned portCHAR * ) &pxManufacturerStringDescriptor, pxRequest->usLength, sizeof( pxManufacturerStringDescriptor ), pdTRUE );
\r
970 case usbPRODUCT_STRING:
\r
971 prvSendControlData( ( unsigned portCHAR * ) &pxProductStringDescriptor, pxRequest->usLength, sizeof( pxProductStringDescriptor ), pdTRUE );
\r
974 case usbCONFIGURATION_STRING:
\r
975 prvSendControlData( ( unsigned portCHAR * ) &pxConfigurationStringDescriptor, pxRequest->usLength, sizeof( pxConfigurationStringDescriptor ), pdTRUE );
\r
978 case usbINTERFACE_STRING:
\r
979 prvSendControlData( ( unsigned portCHAR * ) &pxInterfaceStringDescriptor, pxRequest->usLength, sizeof( pxInterfaceStringDescriptor ), pdTRUE );
\r
983 /* Don't know what this string is. */
\r
991 /* We are not responding to anything else. */
\r
996 /*-----------------------------------------------------------*/
\r
998 static void prvHandleStandardDeviceRequest( xUSB_REQUEST *pxRequest )
\r
1000 unsigned portSHORT usStatus = 0;
\r
1002 switch( pxRequest->ucRequest )
\r
1004 case usbGET_STATUS_REQUEST:
\r
1005 /* Just send two byte dummy status. */
\r
1006 prvSendControlData( ( unsigned portCHAR * ) &usStatus, sizeof( usStatus ), sizeof( usStatus ), pdFALSE );
\r
1009 case usbGET_DESCRIPTOR_REQUEST:
\r
1010 /* Send device descriptor */
\r
1011 prvGetStandardDeviceDescriptor( pxRequest );
\r
1014 case usbGET_CONFIGURATION_REQUEST:
\r
1015 /* Send selected device configuration */
\r
1016 prvSendControlData( ( unsigned portCHAR * ) &ucUSBConfig, sizeof( ucUSBConfig ), sizeof( ucUSBConfig ), pdFALSE );
\r
1019 case usbSET_FEATURE_REQUEST:
\r
1020 prvUSBTransmitNull();
\r
1023 case usbSET_ADDRESS_REQUEST:
\r
1025 /* Acknowledge the SET_ADDRESS, but (according to the manual) we
\r
1026 cannot actually move to the addressed state until we get a TXCOMP
\r
1027 interrupt from this NULL packet. Therefore we just remember the
\r
1028 address and set our state so we know we have received the address. */
\r
1029 prvUSBTransmitNull();
\r
1030 eDriverState = eJUST_GOT_ADDRESS;
\r
1031 ulReceivedAddress = ( unsigned portLONG ) pxRequest->usValue;
\r
1034 case usbSET_CONFIGURATION_REQUEST:
\r
1036 /* Acknowledge the SET_CONFIGURATION, but (according to the manual)
\r
1037 we cannot actually move to the configured state until we get a
\r
1038 TXCOMP interrupt from this NULL packet. Therefore we just remember the
\r
1039 config and set our state so we know we have received the go ahead. */
\r
1040 ucUSBConfig = ( unsigned portCHAR ) ( pxRequest->usValue & 0xff );
\r
1041 eDriverState = eJUST_GOT_CONFIG;
\r
1042 prvUSBTransmitNull();
\r
1047 /* We don't answer to anything else. */
\r
1052 /*-----------------------------------------------------------*/
\r
1054 static void prvHandleClassInterfaceRequest( xUSB_REQUEST *pxRequest )
\r
1056 switch( pxRequest->ucRequest )
\r
1058 case usbSET_IDLE_REQUEST:
\r
1059 prvUSBTransmitNull();
\r
1062 /* This minimal implementation ignores these. */
\r
1063 case usbGET_REPORT_REQUEST:
\r
1064 case usbGET_IDLE_REQUEST:
\r
1065 case usbGET_PROTOCOL_REQUEST:
\r
1066 case usbSET_REPORT_REQUEST:
\r
1067 case usbSET_PROTOCOL_REQUEST:
\r
1074 /*-----------------------------------------------------------*/
\r
1076 static void prvGetStandardInterfaceDescriptor( xUSB_REQUEST *pxRequest )
\r
1078 switch( ( pxRequest->usValue & ( unsigned portSHORT ) 0xff00 ) >> 8 )
\r
1080 case usbHID_REPORT_DESCRIPTOR:
\r
1081 prvSendControlData( ( unsigned portCHAR * ) pxReportDescriptor, pxRequest->usLength, sizeof( pxReportDescriptor ), pdTRUE );
\r
1086 /* Don't expect to send any others. */
\r
1091 /*-----------------------------------------------------------*/
\r
1093 static void prvHandleStandardInterfaceRequest( xUSB_REQUEST *pxRequest )
\r
1095 unsigned portSHORT usStatus = 0;
\r
1097 switch( pxRequest->ucRequest )
\r
1099 case usbGET_STATUS_REQUEST:
\r
1100 /* Send dummy 2 bytes. */
\r
1101 prvSendControlData( ( unsigned portCHAR * ) &usStatus, sizeof( usStatus ), sizeof( usStatus ), pdFALSE );
\r
1104 case usbGET_DESCRIPTOR_REQUEST:
\r
1105 prvGetStandardInterfaceDescriptor( pxRequest );
\r
1108 /* This minimal implementation does not respond to these. */
\r
1109 case usbGET_INTERFACE_REQUEST:
\r
1110 case usbSET_FEATURE_REQUEST:
\r
1111 case usbSET_INTERFACE_REQUEST:
\r
1118 /*-----------------------------------------------------------*/
\r
1120 static void prvHandleStandardEndPointRequest( xUSB_REQUEST *pxRequest )
\r
1122 switch( pxRequest->ucRequest )
\r
1124 /* This minimal implementation does not expect to respond to these. */
\r
1125 case usbGET_STATUS_REQUEST:
\r
1126 case usbCLEAR_FEATURE_REQUEST:
\r
1127 case usbSET_FEATURE_REQUEST:
\r
1134 /*-----------------------------------------------------------*/
\r
1136 static void vInitUSBInterface( void )
\r
1138 volatile unsigned portLONG ulTemp;
\r
1140 /* Create the queue used to communicate between the USB ISR and task. */
\r
1141 xUSBInterruptQueue = xQueueCreate( usbQUEUE_LENGTH + 1, sizeof( xISRStatus * ) );
\r
1143 /* Initialise a few state variables. */
\r
1144 pxCharsForTx.ulNextCharIndex = ( unsigned portLONG ) 0;
\r
1145 ucUSBConfig = ( unsigned portCHAR ) 0;
\r
1146 eDriverState = eNOTHING;
\r
1148 /* HARDWARE SETUP */
\r
1150 /* Set the PLL USB Divider */
\r
1151 AT91C_BASE_CKGR->CKGR_PLLR |= AT91C_CKGR_USBDIV_1;
\r
1153 /* Enables the 48MHz USB clock UDPCK and System Peripheral USB Clock. */
\r
1154 AT91C_BASE_PMC->PMC_SCER = AT91C_PMC_UDP;
\r
1155 AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_UDP);
\r
1157 /* Setup the PIO for the USB pull up resistor. */
\r
1158 AT91F_PIO_CfgOutput(AT91C_BASE_PIOA,AT91C_PIO_PA16);
\r
1160 /* Start without the pullup - this will get set at the end of this
\r
1162 AT91F_PIO_SetOutput( AT91C_BASE_PIOA, AT91C_PIO_PA16 );
\r
1164 /* When using the USB debugger the peripheral registers do not always get
\r
1165 set to the correct default values. To make sure set the relevant registers
\r
1167 AT91C_BASE_UDP->UDP_IDR = ( unsigned portLONG ) 0xffffffff;
\r
1168 AT91C_BASE_UDP->UDP_ICR = ( unsigned portLONG ) 0xffffffff;
\r
1169 AT91C_BASE_UDP->UDP_CSR[ 0 ] = ( unsigned portLONG ) 0x00;
\r
1170 AT91C_BASE_UDP->UDP_CSR[ 1 ] = ( unsigned portLONG ) 0x00;
\r
1171 AT91C_BASE_UDP->UDP_GLBSTATE = 0;
\r
1172 AT91C_BASE_UDP->UDP_FADDR = 0;
\r
1174 /* Enable the transceiver. */
\r
1175 AT91C_UDP_TRANSCEIVER_ENABLE = 0;
\r
1177 /* Enable the USB interrupts - other interrupts get enabled as the
\r
1178 enumeration process progresses. */
\r
1179 AT91F_AIC_ConfigureIt( AT91C_BASE_AIC, AT91C_ID_UDP, usbINTERRUPT_PRIORITY, AT91C_AIC_SRCTYPE_INT_LEVEL_SENSITIVE, ( void (*)( void ) ) vUSBISREntry );
\r
1180 AT91F_AIC_EnableIt( AT91C_BASE_AIC, AT91C_ID_UDP );
\r
1182 /* Wait a short while before making our presence known. */
\r
1183 vTaskDelay( usbINIT_DELAY );
\r
1184 AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, AT91C_PIO_PA16 );
\r
1186 /*-----------------------------------------------------------*/
\r
1188 static void prvSendControlData( unsigned portCHAR *pucData, unsigned portSHORT usRequestedLength, unsigned portLONG ulLengthToSend, portLONG lSendingDescriptor )
\r
1190 if( ( ( unsigned portLONG ) usRequestedLength < ulLengthToSend ) )
\r
1192 /* Cap the data length to that requested. */
\r
1193 ulLengthToSend = ( unsigned portSHORT ) usRequestedLength;
\r
1195 else if( ( ulLengthToSend < ( unsigned portLONG ) usRequestedLength ) && lSendingDescriptor )
\r
1197 /* We are sending a descriptor. If the descriptor is an exact
\r
1198 multiple of the FIFO length then it will have to be terminated
\r
1199 with a NULL packet. Set the state to indicate this if
\r
1201 if( ( ulLengthToSend % usbFIFO_LENGTH ) == 0 )
\r
1203 eDriverState = eSENDING_EVEN_DESCRIPTOR;
\r
1207 /* Here we assume that the previous message has been sent. THERE IS NO
\r
1208 BUFFER OVERFLOW PROTECTION HERE.
\r
1210 Copy the data to send into the buffer as we cannot send it all at once
\r
1211 (if it is greater than 8 bytes in length). */
\r
1212 memcpy( pxCharsForTx.ucTxBuffer, pucData, ulLengthToSend );
\r
1214 /* Reinitialise the buffer index so we start sending from the start of
\r
1216 pxCharsForTx.ulTotalDataLength = ulLengthToSend;
\r
1217 pxCharsForTx.ulNextCharIndex = ( unsigned portLONG ) 0;
\r
1219 /* Send the first 8 bytes now. The rest will get sent in response to
\r
1220 TXCOMP interrupts. */
\r
1221 prvSendNextSegment();
\r
1223 /*-----------------------------------------------------------*/
\r
1225 static void prvSendNextSegment( void )
\r
1227 volatile unsigned portLONG ulNextLength, ulStatus, ulLengthLeftToSend;
\r
1229 /* Is there any data to send? */
\r
1230 if( pxCharsForTx.ulTotalDataLength > pxCharsForTx.ulNextCharIndex )
\r
1232 ulLengthLeftToSend = pxCharsForTx.ulTotalDataLength - pxCharsForTx.ulNextCharIndex;
\r
1234 /* We can only send 8 bytes to the fifo at a time. */
\r
1235 if( ulLengthLeftToSend > usbFIFO_LENGTH )
\r
1237 ulNextLength = usbFIFO_LENGTH;
\r
1241 ulNextLength = ulLengthLeftToSend;
\r
1244 /* Wait until we can place data in the fifo. THERE IS NO TIMEOUT
\r
1246 while( AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] & AT91C_UDP_TXPKTRDY )
\r
1248 vTaskDelay( usbSHORTEST_DELAY );
\r
1251 /* Write the data to the FIFO. */
\r
1252 while( ulNextLength > ( unsigned portLONG ) 0 )
\r
1254 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_0 ] = pxCharsForTx.ucTxBuffer[ pxCharsForTx.ulNextCharIndex ];
\r
1257 pxCharsForTx.ulNextCharIndex++;
\r
1260 /* Start the transmission. */
\r
1261 portENTER_CRITICAL();
\r
1263 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
1264 usbCSR_SET_BIT( &ulStatus, ( ( unsigned portLONG ) 0x10 ) );
\r
1265 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulStatus;
\r
1267 portEXIT_CRITICAL();
\r
1271 /* There is no data to send. If we were sending a descriptor and the
\r
1272 descriptor was an exact multiple of the max packet size then we need
\r
1273 to send a null to terminate the transmission. */
\r
1274 if( eDriverState == eSENDING_EVEN_DESCRIPTOR )
\r
1276 prvUSBTransmitNull();
\r
1277 eDriverState = eNOTHING;
\r