Projects/Magstripe/Magstripe.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2009.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6       www.fourwalledcubicle.com
   7 */
   8
   9 /*
  10   Copyright 2009  Denver Gingerich (denver [at] ossguy [dot] com)
  11   Copyright 2009  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  12
  13   Permission to use, copy, modify, and distribute this software
  14   and its documentation for any purpose and without fee is hereby
  15   granted, provided that the above copyright notice appear in all
  16   copies and that both that the copyright notice and this
  17   permission notice and warranty disclaimer appear in supporting
  18   documentation, and that the name of the author not be used in
  19   advertising or publicity pertaining to distribution of the
  20   software without specific, written prior permission.
  21
  22   The author disclaim all warranties with regard to this
  23   software, including all implied warranties of merchantability
  24   and fitness.  In no event shall the author be liable for any
  25   special, indirect or consequential damages or any damages
  26   whatsoever resulting from loss of use, data or profits, whether
  27   in an action of contract, negligence or other tortious action,
  28   arising out of or in connection with the use or performance of
  29   this software.
  30 */
  31
  32 #include "Magstripe.h"
  33
  34 BitBuffer_t TrackDataBuffers[3];
  35
  36 USB_ClassInfo_HID_t Keyboard_HID_Interface =
  37         {
  38                 .InterfaceNumber         = 0,
  39
  40                 .ReportINEndpointNumber  = KEYBOARD_EPNUM,
  41                 .ReportINEndpointSize    = KEYBOARD_EPSIZE,
  42         };
  43
  44 int main(void)
  45 {
  46         SetupHardware();
  47
  48         for (uint8_t Buffer = 0; Buffer < 3; Buffer++)
  49           BitBuffer_Init(&TrackDataBuffers[Buffer]);
  50
  51         for (;;)
  52         {
  53                 if (Magstripe_GetStatus() & MAG_CARDPRESENT)
  54                   ReadMagstripeData();
  55
  56                 USB_HID_USBTask(&Keyboard_HID_Interface);
  57                 USB_USBTask();
  58         }
  59 }
  60
  61 void SetupHardware(void)
  62 {
  63         /* Disable watchdog if enabled by bootloader/fuses */
  64         MCUSR &= ~(1 << WDRF);
  65         wdt_disable();
  66
  67         /* Disable clock division */
  68         clock_prescale_set(clock_div_1);
  69
  70         /* Hardware Initialization */
  71         Magstripe_Init();
  72         USB_Init();
  73 }
  74
  75 void ReadMagstripeData(void)
  76 {
  77         /* Arrays to hold the buffer pointers, clock and data bit masks for the separate card tracks */
  78         const struct
  79         {
  80                 uint8_t ClockMask;
  81                 uint8_t DataMask;
  82         } TrackInfo[] = {{MAG_T1_CLOCK, MAG_T1_DATA},
  83                          {MAG_T2_CLOCK, MAG_T2_DATA},
  84                          {MAG_T3_CLOCK, MAG_T3_DATA}};
  85
  86         uint8_t Magstripe_Prev = 0;
  87         uint8_t Magstripe_LCL  = Magstripe_GetStatus();
  88
  89         while (Magstripe_LCL & MAG_CARDPRESENT)
  90         {
  91                 for (uint8_t Track = 0; Track < 3; Track++)
  92                 {
  93                         bool DataPinLevel      = ((Magstripe_LCL & TrackInfo[Track].DataMask) != 0);
  94                         bool ClockPinLevel     = ((Magstripe_LCL & TrackInfo[Track].ClockMask) != 0);
  95                         bool ClockLevelChanged = (((Magstripe_LCL ^ Magstripe_Prev) & TrackInfo[Track].ClockMask) != 0);
  96
  97                         if (ClockPinLevel && ClockLevelChanged)
  98                           BitBuffer_StoreNextBit(&TrackDataBuffers[Track], DataPinLevel);
  99                 }
 100
 101                 Magstripe_Prev = Magstripe_LCL;
 102                 Magstripe_LCL  = Magstripe_GetStatus();
 103         }
 104 }
 105
 106 void EVENT_USB_ConfigurationChanged(void)
 107 {
 108         USB_HID_ConfigureEndpoints(&Keyboard_HID_Interface);
 109 }
 110
 111 void EVENT_USB_UnhandledControlPacket(void)
 112 {
 113         USB_HID_ProcessControlPacket(&Keyboard_HID_Interface);
 114 }
 115
 116 void EVENT_USB_StartOfFrame(void)
 117 {
 118         USB_HID_RegisterStartOfFrame(&Keyboard_HID_Interface);
 119 }
 120
 121 uint16_t CALLBACK_USB_HID_CreateNextHIDReport(USB_ClassInfo_HID_t* HIDInterfaceInfo, void* ReportData)
 122 {
 123         static bool IsKeyReleaseReport;
 124         static bool IsNewlineReport;
 125
 126         BitBuffer_t*               Buffer         = NULL;
 127         USB_KeyboardReport_Data_t* KeyboardReport = (USB_KeyboardReport_Data_t*)ReportData;
 128
 129         /* Key reports must be interleaved with 0 Key Code reports to release the keys, or repeated keys will be ignored */
 130         IsKeyReleaseReport = !IsKeyReleaseReport;
 131
 132         if (IsKeyReleaseReport)
 133         {
 134                 KeyboardReport->KeyCode = 0;
 135         }
 136         else if (IsNewlineReport)
 137         {
 138                 IsNewlineReport = false;
 139                 KeyboardReport->KeyCode = KEY_ENTER;
 140         }
 141         else
 142         {
 143                 if (TrackDataBuffers[0].Elements)
 144                   Buffer = &TrackDataBuffers[0];
 145                 else if (TrackDataBuffers[1].Elements)
 146                   Buffer = &TrackDataBuffers[1];
 147                 else if (TrackDataBuffers[2].Elements)
 148                   Buffer = &TrackDataBuffers[2];
 149                 else
 150                   return 0;
 151
 152                 KeyboardReport->KeyCode = BitBuffer_GetNextBit(Buffer) ? KEY_1 : KEY_0;
 153
 154                 /* If buffer now empty, next report must be a newline to seperate track data */
 155                 if (!(Buffer->Elements))
 156                   IsNewlineReport = true;
 157         }
 158
 159         return sizeof(USB_KeyboardReport_Data_t);
 160 }
 161
 162 void CALLBACK_USB_HID_ProcessReceivedHIDReport(USB_ClassInfo_HID_t* HIDInterfaceInfo, void* ReportData, uint16_t ReportSize)
 163 {
 164         // Unused (but mandatory for the HID class driver) in this demo, since there are no Host->Device reports
 165 }