tmk_core/protocol/lufa/LUFA-git/Projects/AVRISP-MKII/Lib/XPROG/XPROGTarget.c

   1 /*
   2              LUFA Library
   3      Copyright (C) Dean Camera, 2014.
   4
   5   dean [at] fourwalledcubicle [dot] com
   6            www.lufa-lib.org
   7 */
   8
   9 /*
  10   Copyright 2014  Dean Camera (dean [at] fourwalledcubicle [dot] com)
  11
  12   Permission to use, copy, modify, distribute, and sell this
  13   software and its documentation for any purpose is hereby granted
  14   without fee, provided that the above copyright notice appear in
  15   all 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 disclaims 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 /** \file
  32  *
  33  *  Target-related functions for the PDI Protocol decoder.
  34  */
  35
  36 #define  INCLUDE_FROM_XPROGTARGET_C
  37 #include "XPROGTarget.h"
  38
  39 #if defined(ENABLE_XPROG_PROTOCOL) || defined(__DOXYGEN__)
  40
  41 /** Flag to indicate if the USART is currently in Tx or Rx mode. */
  42 bool IsSending;
  43
  44 /** Enables the target's PDI interface, holding the target in reset until PDI mode is exited. */
  45 void XPROGTarget_EnableTargetPDI(void)
  46 {
  47         IsSending = false;
  48
  49         /* Set Tx and XCK as outputs, Rx as input */
  50         DDRD |=  (1 << 5) | (1 << 3);
  51         DDRD &= ~(1 << 2);
  52
  53         /* Set DATA line high for at least 90ns to disable /RESET functionality */
  54         PORTD |= (1 << 3);
  55         _delay_us(100);
  56
  57         /* Set up the synchronous USART for XMEGA communications - 8 data bits, even parity, 2 stop bits */
  58         UBRR1  = ((F_CPU / 2 / XPROG_HARDWARE_SPEED) - 1);
  59         UCSR1B = (1 << TXEN1);
  60         UCSR1C = (1 << UMSEL10) | (1 << UPM11) | (1 << USBS1) | (1 << UCSZ11) | (1 << UCSZ10) | (1 << UCPOL1);
  61
  62         /* Send two IDLEs of 12 bits each to enable PDI interface (need at least 16 idle bits) */
  63         XPROGTarget_SendIdle();
  64         XPROGTarget_SendIdle();
  65 }
  66
  67 /** Enables the target's TPI interface, holding the target in reset until TPI mode is exited. */
  68 void XPROGTarget_EnableTargetTPI(void)
  69 {
  70         IsSending = false;
  71
  72         /* Set /RESET line low for at least 400ns to enable TPI functionality */
  73         AUX_LINE_DDR  |=  AUX_LINE_MASK;
  74         AUX_LINE_PORT &= ~AUX_LINE_MASK;
  75         _delay_us(100);
  76
  77         /* Set Tx and XCK as outputs, Rx as input */
  78         DDRD |=  (1 << 5) | (1 << 3);
  79         DDRD &= ~(1 << 2);
  80
  81         /* Set up the synchronous USART for TPI communications - 8 data bits, even parity, 2 stop bits */
  82         UBRR1  = ((F_CPU / 2 / XPROG_HARDWARE_SPEED) - 1);
  83         UCSR1B = (1 << TXEN1);
  84         UCSR1C = (1 << UMSEL10) | (1 << UPM11) | (1 << USBS1) | (1 << UCSZ11) | (1 << UCSZ10) | (1 << UCPOL1);
  85
  86         /* Send two IDLEs of 12 bits each to enable TPI interface (need at least 16 idle bits) */
  87         XPROGTarget_SendIdle();
  88         XPROGTarget_SendIdle();
  89 }
  90
  91 /** Disables the target's PDI interface, exits programming mode and starts the target's application. */
  92 void XPROGTarget_DisableTargetPDI(void)
  93 {
  94         /* Switch to Rx mode to ensure that all pending transmissions are complete */
  95         if (IsSending)
  96           XPROGTarget_SetRxMode();
  97
  98         /* Turn off receiver and transmitter of the USART, clear settings */
  99         UCSR1A  = ((1 << TXC1) | (1 << RXC1));
 100         UCSR1B  = 0;
 101         UCSR1C  = 0;
 102
 103         /* Tristate all pins */
 104         DDRD  &= ~((1 << 5) | (1 << 3));
 105         PORTD &= ~((1 << 5) | (1 << 3) | (1 << 2));
 106 }
 107
 108 /** Disables the target's TPI interface, exits programming mode and starts the target's application. */
 109 void XPROGTarget_DisableTargetTPI(void)
 110 {
 111         /* Switch to Rx mode to ensure that all pending transmissions are complete */
 112         if (IsSending)
 113           XPROGTarget_SetRxMode();
 114
 115         /* Turn off receiver and transmitter of the USART, clear settings */
 116         UCSR1A |= (1 << TXC1) | (1 << RXC1);
 117         UCSR1B  = 0;
 118         UCSR1C  = 0;
 119
 120         /* Set all USART lines as inputs, tristate */
 121         DDRD  &= ~((1 << 5) | (1 << 3));
 122         PORTD &= ~((1 << 5) | (1 << 3) | (1 << 2));
 123
 124         /* Tristate target /RESET line */
 125         AUX_LINE_DDR  &= ~AUX_LINE_MASK;
 126         AUX_LINE_PORT &= ~AUX_LINE_MASK;
 127 }
 128
 129 /** Sends a byte via the USART.
 130  *
 131  *  \param[in] Byte  Byte to send through the USART
 132  */
 133 void XPROGTarget_SendByte(const uint8_t Byte)
 134 {
 135         /* Switch to Tx mode if currently in Rx mode */
 136         if (!(IsSending))
 137           XPROGTarget_SetTxMode();
 138
 139         /* Wait until there is space in the hardware Tx buffer before writing */
 140         while (!(UCSR1A & (1 << UDRE1)));
 141         UCSR1A |= (1 << TXC1);
 142         UDR1    = Byte;
 143 }
 144
 145 /** Receives a byte via the hardware USART, blocking until data is received or timeout expired.
 146  *
 147  *  \return Received byte from the USART
 148  */
 149 uint8_t XPROGTarget_ReceiveByte(void)
 150 {
 151         /* Switch to Rx mode if currently in Tx mode */
 152         if (IsSending)
 153           XPROGTarget_SetRxMode();
 154
 155         /* Wait until a byte has been received before reading */
 156         while (!(UCSR1A & (1 << RXC1)) && TimeoutTicksRemaining);
 157
 158         return UDR1;
 159 }
 160
 161 /** Sends an IDLE via the USART to the attached target, consisting of a full frame of idle bits. */
 162 void XPROGTarget_SendIdle(void)
 163 {
 164         /* Switch to Tx mode if currently in Rx mode */
 165         if (!(IsSending))
 166           XPROGTarget_SetTxMode();
 167
 168         /* Need to do nothing for a full frame to send an IDLE */
 169         for (uint8_t i = 0; i < BITS_IN_USART_FRAME; i++)
 170         {
 171                 /* Wait for a full cycle of the clock */
 172                 while (PIND & (1 << 5));
 173                 while (!(PIND & (1 << 5)));
 174                 while (PIND & (1 << 5));
 175         }
 176 }
 177
 178 static void XPROGTarget_SetTxMode(void)
 179 {
 180         /* Wait for a full cycle of the clock */
 181         while (PIND & (1 << 5));
 182         while (!(PIND & (1 << 5)));
 183         while (PIND & (1 << 5));
 184
 185         PORTD  |=  (1 << 3);
 186         DDRD   |=  (1 << 3);
 187
 188         UCSR1B &= ~(1 << RXEN1);
 189         UCSR1B |=  (1 << TXEN1);
 190
 191         IsSending = true;
 192 }
 193
 194 static void XPROGTarget_SetRxMode(void)
 195 {
 196         while (!(UCSR1A & (1 << TXC1)));
 197         UCSR1A |=  (1 << TXC1);
 198
 199         UCSR1B &= ~(1 << TXEN1);
 200         UCSR1B |=  (1 << RXEN1);
 201
 202         DDRD   &= ~(1 << 3);
 203         PORTD  &= ~(1 << 3);
 204
 205         IsSending = false;
 206 }
 207
 208 #endif
 209