Projects/AVRISP/Lib/PDITarget.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  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, and distribute this software
  13   and its documentation for any purpose and without fee is hereby
  14   granted, provided that the above copyright notice appear in all
  15   copies and that both that the copyright notice and this
  16   permission notice and warranty disclaimer appear in supporting
  17   documentation, and that the name of the author not be used in
  18   advertising or publicity pertaining to distribution of the
  19   software without specific, written prior permission.
  20
  21   The author disclaim all warranties with regard to this
  22   software, including all implied warranties of merchantability
  23   and fitness.  In no event shall the author be liable for any
  24   special, indirect or consequential damages or any damages
  25   whatsoever resulting from loss of use, data or profits, whether
  26   in an action of contract, negligence or other tortious action,
  27   arising out of or in connection with the use or performance of
  28   this software.
  29 */
  30
  31 #if defined(ENABLE_PDI_PROTOCOL) || defined(__DOXYGEN__)
  32
  33 /** \file
  34  *
  35  *  Target-related functions for the PDI Protocol decoder.
  36  */
  37
  38 #define  INCLUDE_FROM_PDITARGET_C
  39 #include "PDITarget.h"
  40
  41 /** Writes a given byte to the attached XMEGA device, using a RS232 frame via software through the
  42  *  PDI interface.
  43  *
  44  *  \param[in] Byte  Byte to send to the attached device
  45  */
  46 void PDITarget_SendByte(uint8_t Byte)
  47 {
  48         uint8_t LogicOneBits = 0;
  49
  50         // One Start Bit
  51         PDIDATA_LINE_PORT &= ~PDIDATA_LINE_MASK;
  52
  53         TOGGLE_PDI_CLOCK;
  54
  55         // Eight Data Bits
  56         for (uint8_t i = 0; i < 8; i++)
  57         {
  58                 if (Byte & 0x01)
  59                 {
  60                         PDIDATA_LINE_PORT &= ~PDIDATA_LINE_MASK;
  61                         LogicOneBits++;
  62                 }
  63                 else
  64                 {
  65                         PDIDATA_LINE_PORT |=  PDIDATA_LINE_MASK;
  66                 }
  67
  68                 Byte >>= 1;
  69
  70                 TOGGLE_PDI_CLOCK;
  71         }
  72
  73         // Even Parity Bit
  74         if (LogicOneBits & 0x01)
  75           PDIDATA_LINE_PORT &= ~PDIDATA_LINE_MASK;
  76         else
  77           PDIDATA_LINE_PORT |=  PDIDATA_LINE_MASK;
  78
  79         TOGGLE_PDI_CLOCK;
  80
  81         // Two Stop Bits
  82         PDIDATA_LINE_PORT |= PDIDATA_LINE_MASK;
  83
  84         TOGGLE_PDI_CLOCK;
  85         TOGGLE_PDI_CLOCK;
  86 }
  87
  88 /** Reads a given byte from the attached XMEGA device, encoded in a RS232 frame through the PDI interface.
  89  *
  90  *  \return Received byte from the attached device
  91  */
  92 uint8_t PDITarget_ReceiveByte(void)
  93 {
  94         uint8_t ReceivedByte = 0;
  95
  96         PDIDATA_LINE_DDR &= ~PDIDATA_LINE_MASK;
  97
  98         // One Start Bit
  99         while (PDIDATA_LINE_PIN & PDIDATA_LINE_MASK);
 100           TOGGLE_PDI_CLOCK;
 101
 102         // Eight Data Bits
 103         for (uint8_t i = 0; i < 8; i++)
 104         {
 105                 if (PDIDATA_LINE_PIN & PDIDATA_LINE_MASK)
 106                         ReceivedByte |= 0x01;
 107
 108                 ReceivedByte <<= 1;
 109
 110                 TOGGLE_PDI_CLOCK;
 111         }
 112
 113         // Even Parity Bit (discarded)
 114         TOGGLE_PDI_CLOCK;
 115
 116         // Two Stop Bits
 117         TOGGLE_PDI_CLOCK;
 118         TOGGLE_PDI_CLOCK;
 119
 120         PDIDATA_LINE_DDR |= PDIDATA_LINE_MASK;
 121
 122         return ReceivedByte;
 123 }
 124
 125 #endif