2 FreeRTOS V5.4.2 - Copyright (C) 2009 Real Time Engineers Ltd.
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4 This file is part of the FreeRTOS distribution.
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6 FreeRTOS is free software; you can redistribute it and/or modify it under
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7 the terms of the GNU General Public License (version 2) as published by the
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8 Free Software Foundation and modified by the FreeRTOS exception.
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9 **NOTE** The exception to the GPL is included to allow you to distribute a
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10 combined work that includes FreeRTOS without being obliged to provide the
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11 source code for proprietary components outside of the FreeRTOS kernel.
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12 Alternative commercial license and support terms are also available upon
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13 request. See the licensing section of http://www.FreeRTOS.org for full
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16 FreeRTOS is distributed in the hope that it will be useful, but WITHOUT
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17 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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18 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
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21 You should have received a copy of the GNU General Public License along
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22 with FreeRTOS; if not, write to the Free Software Foundation, Inc., 59
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23 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
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26 ***************************************************************************
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28 * Looking for a quick start? Then check out the FreeRTOS eBook! *
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29 * See http://www.FreeRTOS.org/Documentation for details *
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31 ***************************************************************************
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35 Please ensure to read the configuration and relevant port sections of the
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36 online documentation.
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38 http://www.FreeRTOS.org - Documentation, latest information, license and
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41 http://www.SafeRTOS.com - A version that is certified for use in safety
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44 http://www.OpenRTOS.com - Commercial support, development, porting,
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45 licensing and training services.
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49 Sample interrupt driven USB device driver. This is a minimal implementation
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50 for demonstration only. Although functional, it is not a full and compliant
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53 The USB device enumerates as a simple 3 axis joystick, and once configured
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54 transmits 3 axis of data which can be viewed from the USB host machine.
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56 This file implements the USB interrupt service routine, and a demo FreeRTOS
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57 task. The interrupt service routine handles the USB hardware - taking a
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58 snapshot of the USB status at the point of the interrupt. The task receives
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59 the status information from the interrupt for processing at the task level.
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61 See the FreeRTOS.org WEB documentation for more information.
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67 + Descriptors that have a length that is an exact multiple of usbFIFO_LENGTH
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68 can now be transmitted. To this end an extra parameter has been
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69 added to the prvSendControlData() function, and the state
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70 eSENDING_EVEN_DESCRIPTOR has been introduced. Thanks to Scott Miller for
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71 assisting with this contribution.
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75 + Replaced the duplicated RX_DATA_BK0 in the interrupt mask with the
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79 /* Standard includes. */
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82 /* Demo board includes. */
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85 /* Scheduler includes. */
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86 #include "FreeRTOS.h"
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91 /* Descriptor type definitions. */
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92 #define usbDESCRIPTOR_TYPE_DEVICE ( 0x01 )
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93 #define usbDESCRIPTOR_TYPE_CONFIGURATION ( 0x02 )
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94 #define usbDESCRIPTOR_TYPE_STRING ( 0x03 )
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96 /* USB request type definitions. */
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97 #define usbGET_REPORT_REQUEST ( 0x01 )
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98 #define usbGET_IDLE_REQUEST ( 0x02 )
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99 #define usbGET_PROTOCOL_REQUEST ( 0x03 )
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100 #define usbSET_REPORT_REQUEST ( 0x09 )
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101 #define usbSET_IDLE_REQUEST ( 0x0A )
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102 #define usbSET_PROTOCOL_REQUEST ( 0x0B )
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103 #define usbGET_CONFIGURATION_REQUEST ( 0x08 )
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104 #define usbGET_STATUS_REQUEST ( 0x00 )
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105 #define usbCLEAR_FEATURE_REQUEST ( 0x01 )
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106 #define usbSET_FEATURE_REQUEST ( 0x03 )
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107 #define usbSET_ADDRESS_REQUEST ( 0x05 )
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108 #define usbGET_DESCRIPTOR_REQUEST ( 0x06 )
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109 #define usbSET_CONFIGURATION_REQUEST ( 0x09 )
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110 #define usbGET_INTERFACE_REQUEST ( 0x0A )
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111 #define usbSET_INTERFACE_REQUEST ( 0x0B )
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114 /* Misc USB definitions. */
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115 #define usbDEVICE_CLASS_VENDOR_SPECIFIC ( 0xFF )
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116 #define usbBUS_POWERED ( 0x80 )
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117 #define usbHID_REPORT_DESCRIPTOR ( 0x22 )
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118 #define AT91C_UDP_TRANSCEIVER_ENABLE ( *( ( unsigned long * ) 0xfffb0074 ) )
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120 /* Index to the various string. */
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121 #define usbLANGUAGE_STRING ( 0 )
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122 #define usbMANUFACTURER_STRING ( 1 )
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123 #define usbPRODUCT_STRING ( 2 )
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124 #define usbCONFIGURATION_STRING ( 3 )
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125 #define usbINTERFACE_STRING ( 4 )
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127 /* Data indexes for reading the request from the xISRStatus.ucFifoData[]
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128 into xUSB_REQUEST. The data order is designed for speed - so looks a
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130 #define usbREQUEST_TYPE_INDEX ( 7 )
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131 #define usbREQUEST_INDEX ( 6 )
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132 #define usbVALUE_HIGH_BYTE ( 4 )
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133 #define usbVALUE_LOW_BYTE ( 5 )
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134 #define usbINDEX_HIGH_BYTE ( 2 )
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135 #define usbINDEX_LOW_BYTE ( 3 )
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136 #define usbLENGTH_HIGH_BYTE ( 0 )
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137 #define usbLENGTH_LOW_BYTE ( 1 )
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139 /* Misc application definitions. */
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140 #define usbINTERRUPT_PRIORITY ( 3 )
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141 #define usbQUEUE_LENGTH ( 0x3 ) /* Must have all bits set! */
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142 #define usbFIFO_LENGTH ( ( unsigned portLONG ) 8 )
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143 #define usbEND_POINT_0 ( 0 )
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144 #define usbEND_POINT_1 ( 1 )
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145 #define usbXUP ( 1 )
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146 #define usbXDOWN ( 2 )
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147 #define usbYUP ( 3 )
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148 #define usbYDOWN ( 4 )
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149 #define usbMAX_COORD ( 120 )
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150 #define usbMAX_TX_MESSAGE_SIZE ( 128 )
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151 #define usbRX_COUNT_MASK ( ( unsigned portLONG ) 0x7ff )
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152 #define AT91C_UDP_STALLSENT AT91C_UDP_ISOERROR
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153 #define usbSHORTEST_DELAY ( ( portTickType ) 1 )
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154 #define usbINIT_DELAY ( ( portTickType ) 500 / portTICK_RATE_MS )
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155 #define usbSHORT_DELAY ( ( portTickType ) 50 / portTICK_RATE_MS )
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156 #define usbEND_POINT_RESET_MASK ( ( unsigned portLONG ) 0x0f )
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157 #define usbDATA_INC ( ( portCHAR ) 5 )
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158 #define usbEXPECTED_NUMBER_OF_BYTES ( ( unsigned portLONG ) 8 )
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160 /* Control request types. */
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161 #define usbSTANDARD_DEVICE_REQUEST ( 0 )
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162 #define usbSTANDARD_INTERFACE_REQUEST ( 1 )
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163 #define usbSTANDARD_END_POINT_REQUEST ( 2 )
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164 #define usbCLASS_INTERFACE_REQUEST ( 5 )
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166 /*-----------------------------------------------------------*/
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168 /* Structure used to take a snapshot of the USB status from within the ISR. */
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169 typedef struct X_ISR_STATUS
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171 unsigned portLONG ulISR;
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172 unsigned portLONG ulCSR0;
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173 unsigned portCHAR ucFifoData[ 8 ];
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176 /* Structure used to hold the received requests. */
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179 unsigned portCHAR ucReqType;
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180 unsigned portCHAR ucRequest;
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181 unsigned portSHORT usValue;
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182 unsigned portSHORT usIndex;
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183 unsigned portSHORT usLength;
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192 eSENDING_EVEN_DESCRIPTOR,
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196 /* Structure used to control the data being sent to the host. */
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199 unsigned portCHAR ucTxBuffer[ usbMAX_TX_MESSAGE_SIZE ];
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200 unsigned portLONG ulNextCharIndex;
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201 unsigned portLONG ulTotalDataLength;
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204 /*-----------------------------------------------------------*/
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207 * The USB interrupt service routine. This takes a snapshot of the USB
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208 * device at the time of the interrupt, clears the interrupts, and posts
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209 * the data to the USB processing task.
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211 __arm void vUSB_ISR( void );
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214 * Called after the bus reset interrupt - this function readies all the
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215 * end points for communication.
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217 static void prvResetEndPoints( void );
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220 * Setup the USB hardware, install the interrupt service routine and
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221 * initialise all the state variables.
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223 static void vInitUSBInterface( void );
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226 * Decode and act upon an interrupt generated by the control end point.
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228 static void prvProcessEndPoint0Interrupt( xISRStatus *pxMessage );
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231 * For simplicity requests are separated into device, interface, class
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232 * interface and end point requests.
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234 * Decode and handle standard device requests originating on the control
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237 static void prvHandleStandardDeviceRequest( xUSB_REQUEST *pxRequest );
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240 * For simplicity requests are separated into device, interface, class
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241 * interface and end point requests.
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243 * Decode and handle standard interface requests originating on the control
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246 static void prvHandleStandardInterfaceRequest( xUSB_REQUEST *pxRequest );
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249 * For simplicity requests are separated into device, interface, class
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250 * interface and end point requests.
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252 * Decode and handle standard end point requests originating on the control
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255 static void prvHandleStandardEndPointRequest( xUSB_REQUEST *pxRequest );
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258 * For simplicity requests are separated into device, interface, class
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259 * interface and end point requests.
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261 * Decode and handle the class interface requests.
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263 static void prvHandleClassInterfaceRequest( xUSB_REQUEST *pxRequest );
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266 * Setup the Tx buffer to send data in response to a control request.
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268 * The data to be transmitted is buffered, the state variables are updated,
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269 * then prvSendNextSegment() is called to start the transmission off. Once
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270 * the first segment has been sent the remaining segments are transmitted
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271 * in response to TXCOMP interrupts until the entire buffer has been
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274 static void prvSendControlData( unsigned portCHAR *pucData, unsigned portSHORT usRequestedLength, unsigned portLONG ulLengthLeftToSend, portLONG lSendingDescriptor );
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277 * Examine the Tx buffer to see if there is any more data to be transmitted.
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279 * If there is data to be transmitted then send the next segment. A segment
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280 * can have a maximum of 8 bytes (this is defined as the maximum for the end
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281 * point by the descriptor). The final segment may be less than 8 bytes if
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282 * the total data length was not an exact multiple of 8.
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284 static void prvSendNextSegment( void );
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287 * A stall condition is forced each time the host makes a request that is not
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288 * supported by this minimal implementation.
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290 * A stall is forced by setting the appropriate bit in the end points control
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291 * and status register.
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293 static void prvSendStall( void );
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296 * A NULL (or zero length packet) is transmitted in acknowledge the reception
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297 * of certain events from the host.
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299 static void prvUSBTransmitNull( void );
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302 * When the host requests a descriptor this function is called to determine
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303 * which descriptor is being requested and start its transmission.
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305 static void prvGetStandardInterfaceDescriptor( xUSB_REQUEST *pxRequest );
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308 * This demo USB device enumerates as a simple 3 axis joystick. Once
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309 * configured this function is periodically called to generate some sample
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312 * The x and y axis are made to move in a square. The z axis is made to
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313 * repeatedly increment up to its maximum.
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315 static void prvTransmitSampleValues( void );
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318 * The created task to handle the USB demo functionality.
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320 void vUSBDemoTask( void *pvParameters );
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322 /*-----------------------------------------------------------*/
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325 - DESCRIPTOR DEFINITIONS -
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328 /* String descriptors used during the enumeration process.
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329 These take the form:
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332 Length of descriptor,
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337 const portCHAR pxLanguageStringDescriptor[] =
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340 usbDESCRIPTOR_TYPE_STRING,
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344 const portCHAR pxManufacturerStringDescriptor[] =
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347 usbDESCRIPTOR_TYPE_STRING,
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359 const portCHAR pxProductStringDescriptor[] =
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362 usbDESCRIPTOR_TYPE_STRING,
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387 const portCHAR pxConfigurationStringDescriptor[] =
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390 usbDESCRIPTOR_TYPE_STRING,
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412 const portCHAR pxInterfaceStringDescriptor[] =
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415 usbDESCRIPTOR_TYPE_STRING,
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433 /* Enumeration descriptors. */
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434 const portCHAR pxReportDescriptor[] =
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436 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */
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437 0x09, 0x04, /* USAGE (Joystick) */
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438 0xa1, 0x01, /* COLLECTION (Application) */
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439 0x05, 0x01, /* USAGE_PAGE (Generic Desktop) */
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440 0x09, 0x01, /* USAGE (Pointer) */
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441 0xa1, 0x00, /* COLLECTION (Physical) */
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442 0x09, 0x30, /* USAGE (X) */
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443 0x09, 0x31, /* USAGE (Y) */
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444 0x09, 0x32, /* USAGE (Z) */
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445 0x15, 0x81, /* LOGICAL_MINIMUM (-127) */
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446 0x25, 0x7f, /* LOGICAL_MAXIMUM (127) */
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447 0x75, 0x08, /* REPORT_SIZE (8) */
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448 0x95, 0x03, /* REPORT_COUNT (3) */
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449 0x81, 0x02, /* INPUT (Data,Var,Abs) */
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450 0xc0, /* END_COLLECTION */
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451 0xc0 /* END_COLLECTION */
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454 const char pxDeviceDescriptor[] =
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456 /* Device descriptor */
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457 0x12, /* bLength */
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458 0x01, /* bDescriptorType */
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459 0x10, 0x01, /* bcdUSBL */
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460 usbDEVICE_CLASS_VENDOR_SPECIFIC, /* bDeviceClass: */
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461 0x00, /* bDeviceSubclass: */
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462 0x00, /* bDeviceProtocol: */
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463 0x08, /* bMaxPacketSize0 */
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464 0xFF, 0xFF, /* idVendorL */
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465 0x01, 0x00, /* idProductL */
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466 0x00, 0x01, /* bcdDeviceL */
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467 usbMANUFACTURER_STRING, /* iManufacturer */
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468 usbPRODUCT_STRING, /* iProduct */
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469 0x00, /* SerialNumber */
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470 0x01 /* bNumConfigs */
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473 const char pxConfigDescriptor[] = {
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474 /* Configuration 1 descriptor */
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475 0x09, /* CbLength */
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476 0x02, /* CbDescriptorType */
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477 0x22, 0x00, /* CwTotalLength 2 EP + Control */
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478 0x01, /* CbNumInterfaces */
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479 0x01, /* CbConfigurationValue */
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480 usbCONFIGURATION_STRING,/* CiConfiguration */
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481 usbBUS_POWERED, /* CbmAttributes Bus powered + Remote Wakeup*/
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482 0x32, /* CMaxPower: 100mA */
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484 /* Joystick Interface Descriptor Requirement */
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485 0x09, /* bLength */
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486 0x04, /* bDescriptorType */
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487 0x00, /* bInterfaceNumber */
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488 0x00, /* bAlternateSetting */
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489 0x01, /* bNumEndpoints */
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490 0x03, /* bInterfaceClass: HID code */
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491 0x00, /* bInterfaceSubclass */
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492 0x00, /* bInterfaceProtocol */
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493 usbINTERFACE_STRING,/* iInterface */
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495 /* HID Descriptor */
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496 0x09, /* bLength */
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497 0x21, /* bDescriptor type: HID Descriptor Type */
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498 0x00, 0x01, /* bcdHID */
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499 0x00, /* bCountryCode */
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500 0x01, /* bNumDescriptors */
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501 usbHID_REPORT_DESCRIPTOR, /* bDescriptorType */
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502 sizeof( pxReportDescriptor ), 0x00, /* wItemLength */
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504 /* Endpoint 1 descriptor */
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505 0x07, /* bLength */
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506 0x05, /* bDescriptorType */
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507 0x81, /* bEndpointAddress, Endpoint 01 - IN */
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508 0x03, /* bmAttributes INT */
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509 0x03, 0x00, /* wMaxPacketSize: 3 bytes (x, y, z) */
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510 0x0A /* bInterval */
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513 /*-----------------------------------------------------------*/
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515 /* File scope state variables. */
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516 static unsigned portCHAR ucUSBConfig = ( unsigned portCHAR ) 0;
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517 static unsigned portLONG ulReceivedAddress = ( unsigned portLONG ) 0;
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518 static eDRIVER_STATE eDriverState = eNOTHING;
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520 /* Array in which the USB interrupt status is passed between the ISR and task. */
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521 static xISRStatus xISRMessages[ usbQUEUE_LENGTH + 1 ];
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523 /* Structure used to control the characters being sent to the host. */
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524 static xTX_MESSAGE pxCharsForTx;
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526 /* Queue used to pass messages between the ISR and the task. */
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527 static xQueueHandle xUSBInterruptQueue;
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529 /* ISR entry has to be written in the asm file as we want a context switch
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530 to occur from within the ISR. See the port documentation on the FreeRTOS.org
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531 WEB site for more information. */
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532 extern void vUSBISREntry( void );
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534 /*-----------------------------------------------------------*/
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536 /* Macros to manipulate the control and status registers. These registers
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537 cannot be accessed using a direct read modify write operation outside of the
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538 ISR as some bits are left unchanged by writing with a 0, and some are left
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539 unchanged by writing with a 1. */
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541 #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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543 #define usbCSR_SET_BIT( pulValueNow, ulBit ) \
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545 /* Set TXCOMP, RX_DATA_BK0, RXSETUP, */ \
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546 /* STALLSENT and RX_DATA_BK1 to 1 so the */ \
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547 /* write has no effect. */ \
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548 ( * ( ( unsigned portLONG * ) pulValueNow ) ) |= ( unsigned portLONG ) 0x4f; \
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550 /* Clear the FORCE_STALL and TXPKTRDY bits */ \
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551 /* so the write has no effect. */ \
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552 ( * ( ( unsigned portLONG * ) pulValueNow ) ) &= ( unsigned portLONG ) 0xffffffcf; \
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554 /* Set whichever bit we want set. */ \
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555 ( * ( ( unsigned portLONG * ) pulValueNow ) ) |= ( ulBit ); \
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558 #define usbCSR_CLEAR_BIT( pulValueNow, ulBit ) \
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560 /* Set TXCOMP, RX_DATA_BK0, RXSETUP, */ \
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561 /* STALLSENT and RX_DATA_BK1 to 1 so the */ \
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562 /* write has no effect. */ \
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563 ( * ( ( unsigned portLONG * ) pulValueNow ) ) |= ( unsigned portLONG ) 0x4f; \
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565 /* Clear the FORCE_STALL and TXPKTRDY bits */ \
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566 /* so the write has no effect. */ \
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567 ( * ( ( unsigned portLONG * ) pulValueNow ) ) &= ( unsigned portLONG ) 0xffffffcf; \
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569 /* Clear whichever bit we want clear. */ \
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570 ( * ( ( unsigned portLONG * ) pulValueNow ) ) &= ( ~ulBit ); \
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573 /*-----------------------------------------------------------*/
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575 __arm void vUSB_ISR( void )
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577 portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
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578 static volatile unsigned portLONG ulNextMessage = 0;
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579 xISRStatus *pxMessage;
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580 unsigned portLONG ulTemp, ulRxBytes;
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582 /* Take the next message from the queue. Note that usbQUEUE_LENGTH *must*
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583 be all 1's, as in 0x01, 0x03, 0x07, etc. */
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584 pxMessage = &( xISRMessages[ ( ulNextMessage & usbQUEUE_LENGTH ) ] );
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587 /* Take a snapshot of the current USB state for processing at the task
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589 pxMessage->ulISR = AT91C_BASE_UDP->UDP_ISR;
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590 pxMessage->ulCSR0 = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
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592 /* Clear the interrupts from the ICR register. The bus end interrupt is
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593 cleared separately as it does not appear in the mask register. */
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594 AT91C_BASE_UDP->UDP_ICR = AT91C_BASE_UDP->UDP_IMR | AT91C_UDP_ENDBUSRES;
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596 /* If there are bytes in the FIFO then we have to retrieve them here.
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597 Ideally this would be done at the task level. However we need to clear the
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598 RXSETUP interrupt before leaving the ISR, and this may cause the data in
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599 the FIFO to be overwritten. Also the DIR bit has to be changed before the
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600 RXSETUP bit is cleared (as per the SAM7 manual). */
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601 ulTemp = pxMessage->ulCSR0;
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603 /* Are there any bytes in the FIFO? */
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604 ulRxBytes = ulTemp >> 16;
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605 ulRxBytes &= usbRX_COUNT_MASK;
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607 /* With this minimal implementation we are only interested in receiving
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608 setup bytes on the control end point. */
\r
609 if( ( ulRxBytes > 0 ) && ( ulTemp & AT91C_UDP_RXSETUP ) )
\r
611 /* Take off 1 for a zero based index. */
\r
612 while( ulRxBytes > 0 )
\r
615 pxMessage->ucFifoData[ ulRxBytes ] = AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_0 ];
\r
618 /* The direction must be changed first. */
\r
619 usbCSR_SET_BIT( &ulTemp, ( AT91C_UDP_DIR ) );
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620 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulTemp;
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623 /* Must write zero's to TXCOMP, STALLSENT, RXSETUP, and the RX DATA
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624 registers to clear the interrupts in the CSR register. */
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625 usbCSR_CLEAR_BIT( &ulTemp, usbINT_CLEAR_MASK );
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626 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulTemp;
\r
628 /* Also clear the interrupts in the CSR1 register. */
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629 ulTemp = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ];
\r
630 usbCSR_CLEAR_BIT( &ulTemp, usbINT_CLEAR_MASK );
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631 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] = ulTemp;
\r
633 /* The message now contains the entire state and optional data from
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634 the USB interrupt. This can now be posted on the Rx queue ready for
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635 processing at the task level. */
\r
636 xQueueSendFromISR( xUSBInterruptQueue, &pxMessage, &xHigherPriorityTaskWoken );
\r
638 /* We may want to switch to the USB task, if this message has made
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639 it the highest priority task that is ready to execute. */
\r
640 portEND_SWITCHING_ISR( xHigherPriorityTaskWoken );
\r
642 /* Clear the AIC ready for the next interrupt. */
\r
643 AT91C_BASE_AIC->AIC_EOICR = 0;
\r
645 /*-----------------------------------------------------------*/
\r
647 void vUSBDemoTask( void *pvParameters )
\r
649 xISRStatus *pxMessage;
\r
651 /* The parameters are not used in this task. */
\r
652 ( void ) pvParameters;
\r
654 /* Init USB device */
\r
655 portENTER_CRITICAL();
\r
656 vInitUSBInterface();
\r
657 portEXIT_CRITICAL();
\r
659 /* Process interrupts as they arrive. The ISR takes a snapshot of the
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660 interrupt status then posts the information on this queue for processing
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661 at the task level. This simple demo implementation only processes
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662 a few interrupt sources. */
\r
665 if( xQueueReceive( xUSBInterruptQueue, &pxMessage, usbSHORT_DELAY ) )
\r
667 if( pxMessage->ulISR & AT91C_UDP_EPINT0 )
\r
669 /* Process end point 0 interrupt. */
\r
670 prvProcessEndPoint0Interrupt( pxMessage );
\r
673 if( pxMessage->ulISR & AT91C_UDP_ENDBUSRES )
\r
675 /* Process an end of bus reset interrupt. */
\r
676 prvResetEndPoints();
\r
681 /* The ISR did not post any data for us to process on the queue, so
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682 just generate and send some sample data. */
\r
683 if( eDriverState == eREADY_TO_SEND )
\r
685 prvTransmitSampleValues();
\r
690 /*-----------------------------------------------------------*/
\r
692 static void prvTransmitSampleValues( void )
\r
694 unsigned portLONG ulStatus;
\r
695 static portLONG lState = usbXUP;
\r
697 /* Variables to hold dummy x, y and z joystick axis data. */
\r
698 static signed portCHAR x = 0, y = 0, z = 0;
\r
700 /* Generate some sample data in the x and y axis - draw a square. */
\r
703 case usbXUP : x += usbDATA_INC;
\r
704 if( x >= usbMAX_COORD )
\r
710 case usbXDOWN : x -= usbDATA_INC;
\r
711 if( x <= -usbMAX_COORD )
\r
717 case usbYUP : y += usbDATA_INC;
\r
718 if( y >= usbMAX_COORD )
\r
724 case usbYDOWN : y -= usbDATA_INC;
\r
725 if( y <= -usbMAX_COORD )
\r
732 /* Just make the z axis go up and down. */
\r
735 /* Can we place data in the fifo? */
\r
736 if( !( AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] & AT91C_UDP_TXPKTRDY ) )
\r
738 /* Write our sample data to the fifo. */
\r
739 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_1 ] = x;
\r
740 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_1 ] = y;
\r
741 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_1 ] = z;
\r
743 /* Send the data. */
\r
744 portENTER_CRITICAL();
\r
746 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ];
\r
747 usbCSR_SET_BIT( &ulStatus, ( AT91C_UDP_TXPKTRDY ) );
\r
748 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] = ulStatus;
\r
750 portEXIT_CRITICAL();
\r
753 /*-----------------------------------------------------------*/
\r
755 static void prvUSBTransmitNull( void )
\r
757 unsigned portLONG ulStatus;
\r
759 /* Wait until the FIFO is free - even though we are not going to use it.
\r
760 THERE IS NO TIMEOUT HERE! */
\r
761 while( AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] & AT91C_UDP_TXPKTRDY )
\r
763 vTaskDelay( usbSHORTEST_DELAY );
\r
766 portENTER_CRITICAL();
\r
768 /* Set the length of data to send to equal the index of the next byte
\r
769 to send. This will prevent the ACK to this NULL packet causing any
\r
770 further data transmissions. */
\r
771 pxCharsForTx.ulTotalDataLength = pxCharsForTx.ulNextCharIndex;
\r
773 /* Set the TXPKTRDY bit to cause a transmission with no data. */
\r
774 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
775 usbCSR_SET_BIT( &ulStatus, ( AT91C_UDP_TXPKTRDY ) );
\r
776 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulStatus;
\r
778 portEXIT_CRITICAL();
\r
780 /*-----------------------------------------------------------*/
\r
782 static void prvSendStall( void )
\r
784 unsigned portLONG ulStatus;
\r
786 portENTER_CRITICAL();
\r
788 /* Force a stall by simply setting the FORCESTALL bit in the CSR. */
\r
789 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
790 usbCSR_SET_BIT( &ulStatus, AT91C_UDP_FORCESTALL );
\r
791 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulStatus;
\r
793 portEXIT_CRITICAL();
\r
795 /*-----------------------------------------------------------*/
\r
797 static void prvResetEndPoints( void )
\r
799 unsigned portLONG ulTemp;
\r
801 eDriverState = eJUST_RESET;
\r
803 /* Reset all the end points. */
\r
804 AT91C_BASE_UDP->UDP_RSTEP = usbEND_POINT_RESET_MASK;
\r
805 AT91C_BASE_UDP->UDP_RSTEP = ( unsigned portLONG ) 0x00;
\r
807 /* Enable data to be sent and received. */
\r
808 AT91C_BASE_UDP->UDP_FADDR = AT91C_UDP_FEN;
\r
810 /* Repair the configuration end point. */
\r
811 portENTER_CRITICAL();
\r
813 ulTemp = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
814 usbCSR_SET_BIT( &ulTemp, ( ( unsigned portLONG ) ( AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_CTRL ) ) );
\r
815 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulTemp;
\r
816 AT91F_UDP_EnableIt( AT91C_BASE_UDP, AT91C_UDP_EPINT0 );
\r
818 portEXIT_CRITICAL();
\r
820 /*-----------------------------------------------------------*/
\r
822 static void prvProcessEndPoint0Interrupt( xISRStatus *pxMessage )
\r
824 if( pxMessage->ulCSR0 & AT91C_UDP_RX_DATA_BK0 )
\r
826 /* We only expect to receive zero length data here as ACK's.
\r
827 Set the data pointer to the end of the current Tx packet to
\r
828 ensure we don't send out any more data. */
\r
829 pxCharsForTx.ulNextCharIndex = pxCharsForTx.ulTotalDataLength;
\r
832 if( pxMessage->ulCSR0 & AT91C_UDP_TXCOMP )
\r
834 /* We received a TX complete interrupt. What we do depends on
\r
835 what we sent to get this interrupt. */
\r
837 if( eDriverState == eJUST_GOT_CONFIG )
\r
839 /* We sent an acknowledgement of a SET_CONFIG request. We
\r
840 are now at the end of the enumeration. */
\r
841 AT91C_BASE_UDP->UDP_GLBSTATE = AT91C_UDP_CONFG;
\r
843 /* Read the end point for data transfer. */
\r
844 portENTER_CRITICAL();
\r
846 unsigned portLONG ulTemp;
\r
848 ulTemp = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ];
\r
849 usbCSR_SET_BIT( &ulTemp, AT91C_UDP_EPEDS | AT91C_UDP_EPTYPE_INT_IN );
\r
850 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_1 ] = ulTemp;
\r
851 AT91F_UDP_EnableIt( AT91C_BASE_UDP, AT91C_UDP_EPINT1 );
\r
853 portEXIT_CRITICAL();
\r
855 eDriverState = eREADY_TO_SEND;
\r
857 else if( eDriverState == eJUST_GOT_ADDRESS )
\r
859 /* We sent an acknowledgement of a SET_ADDRESS request. Move
\r
860 to the addressed state. */
\r
861 if( ulReceivedAddress != ( unsigned portLONG ) 0 )
\r
863 AT91C_BASE_UDP->UDP_GLBSTATE = AT91C_UDP_FADDEN;
\r
867 AT91C_BASE_UDP->UDP_GLBSTATE = 0;
\r
870 AT91C_BASE_UDP->UDP_FADDR = ( AT91C_UDP_FEN | ulReceivedAddress );
\r
871 eDriverState = eNOTHING;
\r
875 /* The TXCOMP was not for any special type of transmission. See
\r
876 if there is any more data to send. */
\r
877 prvSendNextSegment();
\r
881 if( pxMessage->ulCSR0 & AT91C_UDP_RXSETUP )
\r
883 xUSB_REQUEST xRequest;
\r
884 unsigned portCHAR ucRequest;
\r
885 unsigned portLONG ulRxBytes;
\r
887 /* A data packet is available. */
\r
888 ulRxBytes = pxMessage->ulCSR0 >> 16;
\r
889 ulRxBytes &= usbRX_COUNT_MASK;
\r
891 if( ulRxBytes >= usbEXPECTED_NUMBER_OF_BYTES )
\r
893 /* Create an xUSB_REQUEST variable from the raw bytes array. */
\r
895 xRequest.ucReqType = pxMessage->ucFifoData[ usbREQUEST_TYPE_INDEX ];
\r
896 xRequest.ucRequest = pxMessage->ucFifoData[ usbREQUEST_INDEX ];
\r
898 /* NOT PORTABLE CODE! */
\r
899 xRequest.usValue = pxMessage->ucFifoData[ usbVALUE_HIGH_BYTE ];
\r
900 xRequest.usValue <<= 8;
\r
901 xRequest.usValue |= pxMessage->ucFifoData[ usbVALUE_LOW_BYTE ];
\r
903 xRequest.usIndex = pxMessage->ucFifoData[ usbINDEX_HIGH_BYTE ];
\r
904 xRequest.usIndex <<= 8;
\r
905 xRequest.usIndex |= pxMessage->ucFifoData[ usbINDEX_LOW_BYTE ];
\r
907 xRequest.usLength = pxMessage->ucFifoData[ usbLENGTH_HIGH_BYTE ];
\r
908 xRequest.usLength <<= 8;
\r
909 xRequest.usLength |= pxMessage->ucFifoData[ usbLENGTH_LOW_BYTE ];
\r
911 /* Manipulate the ucRequestType and the ucRequest parameters to
\r
912 generate a zero based request selection. This is just done to
\r
913 break up the requests into subsections for clarity. The
\r
914 alternative would be to have more huge switch statement that would
\r
915 be difficult to optimise. */
\r
916 ucRequest = ( ( xRequest.ucReqType & 0x60 ) >> 3 );
\r
917 ucRequest |= ( xRequest.ucReqType & 0x03 );
\r
919 switch( ucRequest )
\r
921 case usbSTANDARD_DEVICE_REQUEST:
\r
922 /* Standard Device request */
\r
923 prvHandleStandardDeviceRequest( &xRequest );
\r
926 case usbSTANDARD_INTERFACE_REQUEST:
\r
927 /* Standard Interface request */
\r
928 prvHandleStandardInterfaceRequest( &xRequest );
\r
931 case usbSTANDARD_END_POINT_REQUEST:
\r
932 /* Standard Endpoint request */
\r
933 prvHandleStandardEndPointRequest( &xRequest );
\r
936 case usbCLASS_INTERFACE_REQUEST:
\r
937 /* Class Interface request */
\r
938 prvHandleClassInterfaceRequest( &xRequest );
\r
941 default: /* This is not something we want to respond to. */
\r
947 /*-----------------------------------------------------------*/
\r
949 static void prvGetStandardDeviceDescriptor( xUSB_REQUEST *pxRequest )
\r
951 /* The type is in the high byte. Return whatever has been requested. */
\r
952 switch( ( pxRequest->usValue & 0xff00 ) >> 8 )
\r
954 case usbDESCRIPTOR_TYPE_DEVICE:
\r
955 prvSendControlData( ( unsigned portCHAR * ) &pxDeviceDescriptor, pxRequest->usLength, sizeof( pxDeviceDescriptor ), pdTRUE );
\r
958 case usbDESCRIPTOR_TYPE_CONFIGURATION:
\r
959 prvSendControlData( ( unsigned portCHAR * ) &( pxConfigDescriptor ), pxRequest->usLength, sizeof( pxConfigDescriptor ), pdTRUE );
\r
962 case usbDESCRIPTOR_TYPE_STRING:
\r
964 /* The index to the string descriptor is the lower byte. */
\r
965 switch( pxRequest->usValue & 0xff )
\r
967 case usbLANGUAGE_STRING:
\r
968 prvSendControlData( ( unsigned portCHAR * ) &pxLanguageStringDescriptor, pxRequest->usLength, sizeof(pxLanguageStringDescriptor), pdTRUE );
\r
971 case usbMANUFACTURER_STRING:
\r
972 prvSendControlData( ( unsigned portCHAR * ) &pxManufacturerStringDescriptor, pxRequest->usLength, sizeof( pxManufacturerStringDescriptor ), pdTRUE );
\r
975 case usbPRODUCT_STRING:
\r
976 prvSendControlData( ( unsigned portCHAR * ) &pxProductStringDescriptor, pxRequest->usLength, sizeof( pxProductStringDescriptor ), pdTRUE );
\r
979 case usbCONFIGURATION_STRING:
\r
980 prvSendControlData( ( unsigned portCHAR * ) &pxConfigurationStringDescriptor, pxRequest->usLength, sizeof( pxConfigurationStringDescriptor ), pdTRUE );
\r
983 case usbINTERFACE_STRING:
\r
984 prvSendControlData( ( unsigned portCHAR * ) &pxInterfaceStringDescriptor, pxRequest->usLength, sizeof( pxInterfaceStringDescriptor ), pdTRUE );
\r
988 /* Don't know what this string is. */
\r
996 /* We are not responding to anything else. */
\r
1001 /*-----------------------------------------------------------*/
\r
1003 static void prvHandleStandardDeviceRequest( xUSB_REQUEST *pxRequest )
\r
1005 unsigned portSHORT usStatus = 0;
\r
1007 switch( pxRequest->ucRequest )
\r
1009 case usbGET_STATUS_REQUEST:
\r
1010 /* Just send two byte dummy status. */
\r
1011 prvSendControlData( ( unsigned portCHAR * ) &usStatus, sizeof( usStatus ), sizeof( usStatus ), pdFALSE );
\r
1014 case usbGET_DESCRIPTOR_REQUEST:
\r
1015 /* Send device descriptor */
\r
1016 prvGetStandardDeviceDescriptor( pxRequest );
\r
1019 case usbGET_CONFIGURATION_REQUEST:
\r
1020 /* Send selected device configuration */
\r
1021 prvSendControlData( ( unsigned portCHAR * ) &ucUSBConfig, sizeof( ucUSBConfig ), sizeof( ucUSBConfig ), pdFALSE );
\r
1024 case usbSET_FEATURE_REQUEST:
\r
1025 prvUSBTransmitNull();
\r
1028 case usbSET_ADDRESS_REQUEST:
\r
1030 /* Acknowledge the SET_ADDRESS, but (according to the manual) we
\r
1031 cannot actually move to the addressed state until we get a TXCOMP
\r
1032 interrupt from this NULL packet. Therefore we just remember the
\r
1033 address and set our state so we know we have received the address. */
\r
1034 prvUSBTransmitNull();
\r
1035 eDriverState = eJUST_GOT_ADDRESS;
\r
1036 ulReceivedAddress = ( unsigned portLONG ) pxRequest->usValue;
\r
1039 case usbSET_CONFIGURATION_REQUEST:
\r
1041 /* Acknowledge the SET_CONFIGURATION, but (according to the manual)
\r
1042 we cannot actually move to the configured state until we get a
\r
1043 TXCOMP interrupt from this NULL packet. Therefore we just remember the
\r
1044 config and set our state so we know we have received the go ahead. */
\r
1045 ucUSBConfig = ( unsigned portCHAR ) ( pxRequest->usValue & 0xff );
\r
1046 eDriverState = eJUST_GOT_CONFIG;
\r
1047 prvUSBTransmitNull();
\r
1052 /* We don't answer to anything else. */
\r
1057 /*-----------------------------------------------------------*/
\r
1059 static void prvHandleClassInterfaceRequest( xUSB_REQUEST *pxRequest )
\r
1061 switch( pxRequest->ucRequest )
\r
1063 case usbSET_IDLE_REQUEST:
\r
1064 prvUSBTransmitNull();
\r
1067 /* This minimal implementation ignores these. */
\r
1068 case usbGET_REPORT_REQUEST:
\r
1069 case usbGET_IDLE_REQUEST:
\r
1070 case usbGET_PROTOCOL_REQUEST:
\r
1071 case usbSET_REPORT_REQUEST:
\r
1072 case usbSET_PROTOCOL_REQUEST:
\r
1079 /*-----------------------------------------------------------*/
\r
1081 static void prvGetStandardInterfaceDescriptor( xUSB_REQUEST *pxRequest )
\r
1083 switch( ( pxRequest->usValue & ( unsigned portSHORT ) 0xff00 ) >> 8 )
\r
1085 case usbHID_REPORT_DESCRIPTOR:
\r
1086 prvSendControlData( ( unsigned portCHAR * ) pxReportDescriptor, pxRequest->usLength, sizeof( pxReportDescriptor ), pdTRUE );
\r
1091 /* Don't expect to send any others. */
\r
1096 /*-----------------------------------------------------------*/
\r
1098 static void prvHandleStandardInterfaceRequest( xUSB_REQUEST *pxRequest )
\r
1100 unsigned portSHORT usStatus = 0;
\r
1102 switch( pxRequest->ucRequest )
\r
1104 case usbGET_STATUS_REQUEST:
\r
1105 /* Send dummy 2 bytes. */
\r
1106 prvSendControlData( ( unsigned portCHAR * ) &usStatus, sizeof( usStatus ), sizeof( usStatus ), pdFALSE );
\r
1109 case usbGET_DESCRIPTOR_REQUEST:
\r
1110 prvGetStandardInterfaceDescriptor( pxRequest );
\r
1113 /* This minimal implementation does not respond to these. */
\r
1114 case usbGET_INTERFACE_REQUEST:
\r
1115 case usbSET_FEATURE_REQUEST:
\r
1116 case usbSET_INTERFACE_REQUEST:
\r
1123 /*-----------------------------------------------------------*/
\r
1125 static void prvHandleStandardEndPointRequest( xUSB_REQUEST *pxRequest )
\r
1127 switch( pxRequest->ucRequest )
\r
1129 /* This minimal implementation does not expect to respond to these. */
\r
1130 case usbGET_STATUS_REQUEST:
\r
1131 case usbCLEAR_FEATURE_REQUEST:
\r
1132 case usbSET_FEATURE_REQUEST:
\r
1139 /*-----------------------------------------------------------*/
\r
1141 static void vInitUSBInterface( void )
\r
1143 volatile unsigned portLONG ulTemp;
\r
1145 /* Create the queue used to communicate between the USB ISR and task. */
\r
1146 xUSBInterruptQueue = xQueueCreate( usbQUEUE_LENGTH + 1, sizeof( xISRStatus * ) );
\r
1148 /* Initialise a few state variables. */
\r
1149 pxCharsForTx.ulNextCharIndex = ( unsigned portLONG ) 0;
\r
1150 ucUSBConfig = ( unsigned portCHAR ) 0;
\r
1151 eDriverState = eNOTHING;
\r
1153 /* HARDWARE SETUP */
\r
1155 /* Set the PLL USB Divider */
\r
1156 AT91C_BASE_CKGR->CKGR_PLLR |= AT91C_CKGR_USBDIV_1;
\r
1158 /* Enables the 48MHz USB clock UDPCK and System Peripheral USB Clock. */
\r
1159 AT91C_BASE_PMC->PMC_SCER = AT91C_PMC_UDP;
\r
1160 AT91C_BASE_PMC->PMC_PCER = (1 << AT91C_ID_UDP);
\r
1162 /* Setup the PIO for the USB pull up resistor. */
\r
1163 AT91F_PIO_CfgOutput(AT91C_BASE_PIOA,AT91C_PIO_PA16);
\r
1165 /* Start without the pullup - this will get set at the end of this
\r
1167 AT91F_PIO_SetOutput( AT91C_BASE_PIOA, AT91C_PIO_PA16 );
\r
1169 /* When using the USB debugger the peripheral registers do not always get
\r
1170 set to the correct default values. To make sure set the relevant registers
\r
1172 AT91C_BASE_UDP->UDP_IDR = ( unsigned portLONG ) 0xffffffff;
\r
1173 AT91C_BASE_UDP->UDP_ICR = ( unsigned portLONG ) 0xffffffff;
\r
1174 AT91C_BASE_UDP->UDP_CSR[ 0 ] = ( unsigned portLONG ) 0x00;
\r
1175 AT91C_BASE_UDP->UDP_CSR[ 1 ] = ( unsigned portLONG ) 0x00;
\r
1176 AT91C_BASE_UDP->UDP_GLBSTATE = 0;
\r
1177 AT91C_BASE_UDP->UDP_FADDR = 0;
\r
1179 /* Enable the transceiver. */
\r
1180 AT91C_UDP_TRANSCEIVER_ENABLE = 0;
\r
1182 /* Enable the USB interrupts - other interrupts get enabled as the
\r
1183 enumeration process progresses. */
\r
1184 AT91F_AIC_ConfigureIt( AT91C_BASE_AIC, AT91C_ID_UDP, usbINTERRUPT_PRIORITY, AT91C_AIC_SRCTYPE_INT_LEVEL_SENSITIVE, ( void (*)( void ) ) vUSBISREntry );
\r
1185 AT91F_AIC_EnableIt( AT91C_BASE_AIC, AT91C_ID_UDP );
\r
1187 /* Wait a short while before making our presence known. */
\r
1188 vTaskDelay( usbINIT_DELAY );
\r
1189 AT91F_PIO_ClearOutput(AT91C_BASE_PIOA, AT91C_PIO_PA16 );
\r
1191 /*-----------------------------------------------------------*/
\r
1193 static void prvSendControlData( unsigned portCHAR *pucData, unsigned portSHORT usRequestedLength, unsigned portLONG ulLengthToSend, portLONG lSendingDescriptor )
\r
1195 if( ( ( unsigned portLONG ) usRequestedLength < ulLengthToSend ) )
\r
1197 /* Cap the data length to that requested. */
\r
1198 ulLengthToSend = ( unsigned portSHORT ) usRequestedLength;
\r
1200 else if( ( ulLengthToSend < ( unsigned portLONG ) usRequestedLength ) && lSendingDescriptor )
\r
1202 /* We are sending a descriptor. If the descriptor is an exact
\r
1203 multiple of the FIFO length then it will have to be terminated
\r
1204 with a NULL packet. Set the state to indicate this if
\r
1206 if( ( ulLengthToSend % usbFIFO_LENGTH ) == 0 )
\r
1208 eDriverState = eSENDING_EVEN_DESCRIPTOR;
\r
1212 /* Here we assume that the previous message has been sent. THERE IS NO
\r
1213 BUFFER OVERFLOW PROTECTION HERE.
\r
1215 Copy the data to send into the buffer as we cannot send it all at once
\r
1216 (if it is greater than 8 bytes in length). */
\r
1217 memcpy( pxCharsForTx.ucTxBuffer, pucData, ulLengthToSend );
\r
1219 /* Reinitialise the buffer index so we start sending from the start of
\r
1221 pxCharsForTx.ulTotalDataLength = ulLengthToSend;
\r
1222 pxCharsForTx.ulNextCharIndex = ( unsigned portLONG ) 0;
\r
1224 /* Send the first 8 bytes now. The rest will get sent in response to
\r
1225 TXCOMP interrupts. */
\r
1226 prvSendNextSegment();
\r
1228 /*-----------------------------------------------------------*/
\r
1230 static void prvSendNextSegment( void )
\r
1232 volatile unsigned portLONG ulNextLength, ulStatus, ulLengthLeftToSend;
\r
1234 /* Is there any data to send? */
\r
1235 if( pxCharsForTx.ulTotalDataLength > pxCharsForTx.ulNextCharIndex )
\r
1237 ulLengthLeftToSend = pxCharsForTx.ulTotalDataLength - pxCharsForTx.ulNextCharIndex;
\r
1239 /* We can only send 8 bytes to the fifo at a time. */
\r
1240 if( ulLengthLeftToSend > usbFIFO_LENGTH )
\r
1242 ulNextLength = usbFIFO_LENGTH;
\r
1246 ulNextLength = ulLengthLeftToSend;
\r
1249 /* Wait until we can place data in the fifo. THERE IS NO TIMEOUT
\r
1251 while( AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] & AT91C_UDP_TXPKTRDY )
\r
1253 vTaskDelay( usbSHORTEST_DELAY );
\r
1256 /* Write the data to the FIFO. */
\r
1257 while( ulNextLength > ( unsigned portLONG ) 0 )
\r
1259 AT91C_BASE_UDP->UDP_FDR[ usbEND_POINT_0 ] = pxCharsForTx.ucTxBuffer[ pxCharsForTx.ulNextCharIndex ];
\r
1262 pxCharsForTx.ulNextCharIndex++;
\r
1265 /* Start the transmission. */
\r
1266 portENTER_CRITICAL();
\r
1268 ulStatus = AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ];
\r
1269 usbCSR_SET_BIT( &ulStatus, ( ( unsigned portLONG ) 0x10 ) );
\r
1270 AT91C_BASE_UDP->UDP_CSR[ usbEND_POINT_0 ] = ulStatus;
\r
1272 portEXIT_CRITICAL();
\r
1276 /* There is no data to send. If we were sending a descriptor and the
\r
1277 descriptor was an exact multiple of the max packet size then we need
\r
1278 to send a null to terminate the transmission. */
\r
1279 if( eDriverState == eSENDING_EVEN_DESCRIPTOR )
\r
1281 prvUSBTransmitNull();
\r
1282 eDriverState = eNOTHING;
\r