Atmel megaAVR控制器 串行引导Bootloader
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开始研究下Bootloader的代码结构
2015.1.9
粗略看了下，Bootloader主要做了下板卡的初始化 -----> 然后进入for( ; ; )死循环 -----> 循环刷新串口数据 -----> 根据数据做出不同应答 -----> 如果有写数据，则将数据存入buffer -----> 从buffer 写入EEPROM -----> 跳转到 app_start() 处执行
写入 EEPROM 的代码过程需要确定。
/**********************************************************//* Serial Bootloader for Atmel megaAVR Controllers *//* *//* tested with ATmega8, ATmega128 and ATmega168 *//* should work with other mega's, see code for details *//* *//* ATmegaBOOT.c *//* *//* *//* 20090308: integrated Mega changes into main bootloader *//* source by D. Mellis *//* 20080930: hacked for Arduino Mega (with the 1280 *//* processor, backwards compatible) *//* by D. Cuartielles *//* 20070626: hacked for Arduino Diecimila (which auto- *//* resets when a USB connection is made to it) *//* by D. Mellis *//* 20060802: hacked for Arduino by D. Cuartielles *//* based on a previous hack by D. Mellis *//* and D. Cuartielles *//* *//* Monitor and debug functions were added to the original *//* code by Dr. Erik Lins, chip45.com. (See below) *//* *//* Thanks to Karl Pitrich for fixing a bootloader pin *//* problem and more informative LED blinking! *//* *//* For the latest version see: *//* http://www.chip45.com/ *//* *//* ------------------------------------------------------ *//* *//* based on stk500boot.c *//* Copyright (c) 2003, Jason P. Kyle *//* All rights reserved. *//* see avr1.org for original file and information *//* *//* This program is free software; you can redistribute it *//* and/or modify it under the terms of the GNU General *//* Public License as published by the Free Software *//* Foundation; either version 2 of the License, or *//* (at your option) any later version. *//* *//* This program is distributed in the hope that it will *//* be useful, but WITHOUT ANY WARRANTY; without even the *//* implied warranty of MERCHANTABILITY or FITNESS FOR A *//* PARTICULAR PURPOSE. See the GNU General Public *//* License for more details. *//* *//* You should have received a copy of the GNU General *//* Public License along with this program; if not, write *//* to the Free Software Foundation, Inc., *//* 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA *//* *//* Licence can be viewed at *//* http://www.fsf.org/licenses/gpl.txt *//* *//* Target = Atmel AVR m128,m64,m32,m16,m8,m162,m163,m169, *//* m8515,m8535. ATmega161 has a very small boot block so *//* isn't supported. *//* *//* Tested with m168 *//**********************************************************//* $Id$ *//* some includes */#include <inttypes.h>#include <avr/io.h>#include <avr/pgmspace.h>#include <avr/interrupt.h>#include <avr/wdt.h>#include <util/delay.h>/* the current avr-libc eeprom functions do not support the ATmega168 *//* own eeprom write/read functions are used instead */#if !defined(__AVR_ATmega168__) || !defined(__AVR_ATmega328P__)#include <avr/eeprom.h>#endif/* Use the F_CPU defined in Makefile *//* 20060803: hacked by DojoCorp *//* 20070626: hacked by David A. Mellis to decrease waiting time for auto-reset *//* set the waiting time for the bootloader *//* get this from the Makefile instead *//* #define MAX_TIME_COUNT (F_CPU>>4) *//* 20070707: hacked by David A. Mellis - after this many errors give up and launch application */#define MAX_ERROR_COUNT 5/* set the UART baud rate *//* 20060803: hacked by DojoCorp *///#define BAUD_RATE 115200#ifndef BAUD_RATE#define BAUD_RATE 19200#endif/* SW_MAJOR and MINOR needs to be updated from time to time to avoid warning message from AVR Studio *//* never allow AVR Studio to do an update !!!! */#define HW_VER 0x02#define SW_MAJOR 0x01#define SW_MINOR 0x10/* Adjust to suit whatever pin your hardware uses to enter the bootloader *//* ATmega128 has two UARTS so two pins are used to enter bootloader and select UART *//* ATmega1280 has four UARTS, but for Arduino Mega, we will only use RXD0 to get code *//* BL0... means UART0, BL1... means UART1 */#ifdef __AVR_ATmega128__#define BL_DDR DDRF#define BL_PORT PORTF#define BL_PIN PINF#define BL0 PINF7#define BL1 PINF6#elif defined __AVR_ATmega1280__ /* we just don't do anything for the MEGA and enter bootloader on reset anyway*/#else/* other ATmegas have only one UART, so only one pin is defined to enter bootloader */#define BL_DDR DDRD#define BL_PORT PORTD#define BL_PIN PIND#define BL PIND6#endif/* onboard LED is used to indicate, that the bootloader was entered (3x flashing) *//* if monitor functions are included, LED goes on after monitor was entered */#if defined __AVR_ATmega128__ || defined __AVR_ATmega1280__/* Onboard LED is connected to pin PB7 (e.g. Crumb128, PROBOmega128, Savvy128, Arduino Mega) */#define LED_DDR DDRB#define LED_PORT PORTB#define LED_PIN PINB#define LED PINB7#else/* Onboard LED is connected to pin PB5 in Arduino NG, Diecimila, and Duomilanuove */ /* other boards like e.g. Crumb8, Crumb168 are using PB2 */#define LED_DDR DDRB#define LED_PORT PORTB#define LED_PIN PINB#define LED PINB5#endif/* monitor functions will only be compiled when using ATmega128, due to bootblock size constraints */#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)#define MONITOR 1#endif/* define various device id's *//* manufacturer byte is always the same */#define SIG10x1E// Yep, Atmel is the only manufacturer of AVR micros. Single source :(#if defined __AVR_ATmega1280__#define SIG20x97#define SIG30x03#define PAGE_SIZE0x80U//128 words#elif defined __AVR_ATmega1281__#define SIG20x97#define SIG30x04#define PAGE_SIZE0x80U//128 words#elif defined __AVR_ATmega128__#define SIG20x97#define SIG30x02#define PAGE_SIZE0x80U//128 words#elif defined __AVR_ATmega64__#define SIG20x96#define SIG30x02#define PAGE_SIZE0x80U//128 words#elif defined __AVR_ATmega32__#define SIG20x95#define SIG30x02#define PAGE_SIZE0x40U//64 words#elif defined __AVR_ATmega16__#define SIG20x94#define SIG30x03#define PAGE_SIZE0x40U//64 words#elif defined __AVR_ATmega8__#define SIG20x93#define SIG30x07#define PAGE_SIZE0x20U//32 words#elif defined __AVR_ATmega88__#define SIG20x93#define SIG30x0a#define PAGE_SIZE0x20U//32 words#elif defined __AVR_ATmega168__#define SIG20x94#define SIG30x06#define PAGE_SIZE0x40U//64 words#elif defined __AVR_ATmega328P__#define SIG20x95#define SIG30x0F#define PAGE_SIZE0x40U//64 words#elif defined __AVR_ATmega162__#define SIG20x94#define SIG30x04#define PAGE_SIZE0x40U//64 words#elif defined __AVR_ATmega163__#define SIG20x94#define SIG30x02#define PAGE_SIZE0x40U//64 words#elif defined __AVR_ATmega169__#define SIG20x94#define SIG30x05#define PAGE_SIZE0x40U//64 words#elif defined __AVR_ATmega8515__#define SIG20x93#define SIG30x06#define PAGE_SIZE0x20U//32 words#elif defined __AVR_ATmega8535__#define SIG20x93#define SIG30x08#define PAGE_SIZE0x20U//32 words#endif/* function prototypes */void putch(char);char getch(void);void getNch(uint8_t);void byte_response(uint8_t);void nothing_response(void);char gethex(void);void puthex(char);void flash_led(uint8_t);/* some variables */union address_union {uint16_t word;uint8_t byte[2];} address;union length_union {uint16_t word;uint8_t byte[2];} length;struct flags_struct {unsigned eeprom : 1;unsigned rampz : 1;} flags;uint8_t buff[256];uint8_t address_high;uint8_t pagesz=0x80;uint8_t i;uint8_t bootuart = 0;uint8_t error_count = 0;void (*app_start)(void) = 0x0000;/* main program starts here */int main(void){uint8_t ch,ch2;uint16_t w;#ifdef WATCHDOG_MODSch = MCUSR;MCUSR = 0;WDTCSR |= _BV(WDCE) | _BV(WDE);WDTCSR = 0;// Check if the WDT was used to reset, in which case we dont bootload and skip straight to the code. woot.if (! (ch & _BV(EXTRF))) // if its a not an external reset...app_start(); // skip bootloader#elseasm volatile("nop\n\t");#endif/* set pin direction for bootloader pin and enable pullup *//* for ATmega128, two pins need to be initialized */#ifdef __AVR_ATmega128__BL_DDR &= ~_BV(BL0);BL_DDR &= ~_BV(BL1);BL_PORT |= _BV(BL0);BL_PORT |= _BV(BL1);#else/* We run the bootloader regardless of the state of this pin. Thus, don'tput it in a different state than the other pins. --DAM, 070709This also applies to Arduino Mega -- DC, 080930BL_DDR &= ~_BV(BL);BL_PORT |= _BV(BL);*/#endif#ifdef __AVR_ATmega128__/* check which UART should be used for booting */if(bit_is_clear(BL_PIN, BL0)) {bootuart = 1;}else if(bit_is_clear(BL_PIN, BL1)) {bootuart = 2;}#endif#if defined __AVR_ATmega1280__/* the mega1280 chip has four serial ports ... we could eventually use any of them, or not? *//* however, we don't wanna confuse people, to avoid making a mess, we will stick to RXD0, TXD0 */bootuart = 1;#endif/* check if flash is programmed already, if not start bootloader anyway */if(pgm_read_byte_near(0x0000) != 0xFF) {#ifdef __AVR_ATmega128__/* no UART was selected, start application */if(!bootuart) {app_start();}#else/* check if bootloader pin is set low *//* we don't start this part neither for the m8, nor m168 *///if(bit_is_set(BL_PIN, BL)) {// app_start();// }#endif}#ifdef __AVR_ATmega128__ /* no bootuart was selected, default to uart 0 */if(!bootuart) {bootuart = 1;}#endif/* initialize UART(s) depending on CPU defined */#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)if(bootuart == 1) {UBRR0L = (uint8_t)(F_CPU/(BAUD_RATE*16L)-1);UBRR0H = (F_CPU/(BAUD_RATE*16L)-1) >> 8;UCSR0A = 0x00;UCSR0C = 0x06;UCSR0B = _BV(TXEN0)|_BV(RXEN0);}if(bootuart == 2) {UBRR1L = (uint8_t)(F_CPU/(BAUD_RATE*16L)-1);UBRR1H = (F_CPU/(BAUD_RATE*16L)-1) >> 8;UCSR1A = 0x00;UCSR1C = 0x06;UCSR1B = _BV(TXEN1)|_BV(RXEN1);}#elif defined __AVR_ATmega163__UBRR = (uint8_t)(F_CPU/(BAUD_RATE*16L)-1);UBRRHI = (F_CPU/(BAUD_RATE*16L)-1) >> 8;UCSRA = 0x00;UCSRB = _BV(TXEN)|_BV(RXEN);#elif defined(__AVR_ATmega168__) || defined(__AVR_ATmega328P__)#ifdef DOUBLE_SPEEDUCSR0A = (1<<U2X0); //Double speed mode USART0UBRR0L = (uint8_t)(F_CPU/(BAUD_RATE*8L)-1);UBRR0H = (F_CPU/(BAUD_RATE*8L)-1) >> 8;#elseUBRR0L = (uint8_t)(F_CPU/(BAUD_RATE*16L)-1);UBRR0H = (F_CPU/(BAUD_RATE*16L)-1) >> 8;#endifUCSR0B = (1<<RXEN0) | (1<<TXEN0);UCSR0C = (1<<UCSZ00) | (1<<UCSZ01);/* Enable internal pull-up resistor on pin D0 (RX), in orderto supress line noise that prevents the bootloader fromtiming out (DAM: 20070509) */DDRD &= ~_BV(PIND0);PORTD |= _BV(PIND0);#elif defined __AVR_ATmega8__/* m8 */UBRRH = (((F_CPU/BAUD_RATE)/16)-1)>>8; // set baud rateUBRRL = (((F_CPU/BAUD_RATE)/16)-1);UCSRB = (1<<RXEN)|(1<<TXEN); // enable Rx & TxUCSRC = (1<<URSEL)|(1<<UCSZ1)|(1<<UCSZ0); // config USART; 8N1#else/* m16,m32,m169,m8515,m8535 */UBRRL = (uint8_t)(F_CPU/(BAUD_RATE*16L)-1);UBRRH = (F_CPU/(BAUD_RATE*16L)-1) >> 8;UCSRA = 0x00;UCSRC = 0x06;UCSRB = _BV(TXEN)|_BV(RXEN);#endif#if defined __AVR_ATmega1280__/* Enable internal pull-up resistor on pin D0 (RX), in orderto supress line noise that prevents the bootloader fromtiming out (DAM: 20070509) *//* feature added to the Arduino Mega --DC: 080930 */DDRE &= ~_BV(PINE0);PORTE |= _BV(PINE0);#endif/* set LED pin as output */LED_DDR |= _BV(LED);/* flash onboard LED to signal entering of bootloader */#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)// 4x for UART0, 5x for UART1flash_led(NUM_LED_FLASHES + bootuart);#elseflash_led(NUM_LED_FLASHES);#endif/* 20050803: by DojoCorp, this is one of the parts provoking the system to stop listening, cancelled from the original *///putch('\0');/* forever loop */for (;;) {/* get character from UART */ch = getch();/* A bunch of if...else if... gives smaller code than switch...case ! *//* Hello is anyone home ? */ if(ch=='0') {nothing_response();}/* Request programmer ID *//* Not using PROGMEM string due to boot block in m128 being beyond 64kB boundry *//* Would need to selectively manipulate RAMPZ, and it's only 9 characters anyway so who cares. */else if(ch=='1') {if (getch() == ' ') {putch(0x14);putch('A');putch('V');putch('R');putch(' ');putch('I');putch('S');putch('P');putch(0x10);} else {if (++error_count == MAX_ERROR_COUNT)app_start();}}/* AVR ISP/STK500 board commands DON'T CARE so default nothing_response */else if(ch=='@') {ch2 = getch();if (ch2>0x85) getch();nothing_response();}/* AVR ISP/STK500 board requests */else if(ch=='A') {ch2 = getch();if(ch2==0x80) byte_response(HW_VER);// Hardware versionelse if(ch2==0x81) byte_response(SW_MAJOR);// Software major versionelse if(ch2==0x82) byte_response(SW_MINOR);// Software minor versionelse if(ch2==0x98) byte_response(0x03);// Unknown but seems to be required by avr studio 3.56else byte_response(0x00);// Covers various unnecessary responses we don't care about}/* Device Parameters DON'T CARE, DEVICE IS FIXED */else if(ch=='B') {getNch(20);nothing_response();}/* Parallel programming stuff DON'T CARE */else if(ch=='E') {getNch(5);nothing_response();}/* P: Enter programming mode *//* R: Erase device, don't care as we will erase one page at a time anyway. */else if(ch=='P' || ch=='R') {nothing_response();}/* Leave programming mode */else if(ch=='Q') {nothing_response();#ifdef WATCHDOG_MODS// autoreset via watchdog (sneaky!)WDTCSR = _BV(WDE);while (1); // 16 ms#endif}/* Set address, little endian. EEPROM in bytes, FLASH in words *//* Perhaps extra address bytes may be added in future to support > 128kB FLASH. *//* This might explain why little endian was used here, big endian used everywhere else. */else if(ch=='U') {address.byte[0] = getch();address.byte[1] = getch();nothing_response();}/* Universal SPI programming command, disabled. Would be used for fuses and lock bits. */else if(ch=='V') {if (getch() == 0x30) {getch();ch = getch();getch();if (ch == 0) {byte_response(SIG1);} else if (ch == 1) {byte_response(SIG2); } else {byte_response(SIG3);} } else {getNch(3);byte_response(0x00);}}/* Write memory, length is big endian and is in bytes */else if(ch=='d') {length.byte[1] = getch();length.byte[0] = getch();flags.eeprom = 0;if (getch() == 'E') flags.eeprom = 1;for (w=0;w<length.word;w++) {buff[w] = getch(); // Store data in buffer, can't keep up with serial data stream whilst programming pages}if (getch() == ' ') {if (flags.eeprom) { //Write to EEPROM one byte at a timeaddress.word <<= 1;for(w=0;w<length.word;w++) {#if defined(__AVR_ATmega168__) || defined(__AVR_ATmega328P__)while(EECR & (1<<EEPE));EEAR = (uint16_t)(void *)address.word;EEDR = buff[w];EECR |= (1<<EEMPE);EECR |= (1<<EEPE);#elseeeprom_write_byte((void *)address.word,buff[w]);#endifaddress.word++;}}else { //Write to FLASH one page at a timeif (address.byte[1]>127) address_high = 0x01;//Only possible with m128, m256 will need 3rd address byte. FIXMEelse address_high = 0x00;#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__) || defined(__AVR_ATmega1281__)RAMPZ = address_high;#endifaddress.word = address.word << 1; //address * 2 -> byte location/* if ((length.byte[0] & 0x01) == 0x01) length.word++;//Even up an odd number of bytes */if ((length.byte[0] & 0x01)) length.word++;//Even up an odd number of bytescli();//Disable interrupts, just to be sure#if defined(__AVR_ATmega1280__) || defined(__AVR_ATmega1281__)while(bit_is_set(EECR,EEPE));//Wait for previous EEPROM writes to complete#elsewhile(bit_is_set(EECR,EEWE));//Wait for previous EEPROM writes to complete#endifasm volatile( "clrr17\n\t"//page_word_count "ldsr30,address\n\t"//Address of FLASH location (in bytes) "ldsr31,address+1\n\t" "ldir28,lo8(buff)\n\t"//Start of buffer array in RAM "ldir29,hi8(buff)\n\t" "ldsr24,length\n\t"//Length of data to be written (in bytes) "ldsr25,length+1\n\t" "length_loop:\n\t"//Main loop, repeat for number of words in block "cpir17,0x00\n\t"//If page_word_count=0 then erase page "brneno_page_erase\n\t" "wait_spm1:\n\t" "ldsr16,%0\n\t"//Wait for previous spm to complete "andir16,1 \n\t" "cpir16,1 \n\t" "breqwait_spm1 \n\t" "ldir16,0x03\n\t"//Erase page pointed to by Z "sts%0,r16\n\t" "spm\n\t" #ifdef __AVR_ATmega163__ ".word 0xFFFF\n\t" "nop\n\t"#endif "wait_spm2:\n\t" "ldsr16,%0\n\t"//Wait for previous spm to complete "andir16,1 \n\t" "cpir16,1 \n\t" "breqwait_spm2 \n\t" "ldir16,0x11\n\t"//Re-enable RWW section "sts%0,r16\n\t" "spm\n\t"#ifdef __AVR_ATmega163__ ".word 0xFFFF\n\t" "nop\n\t"#endif "no_page_erase:\n\t" "ldr0,Y+\n\t"//Write 2 bytes into page buffer "ldr1,Y+\n\t" "wait_spm3:\n\t" "ldsr16,%0\n\t"//Wait for previous spm to complete "andir16,1 \n\t" "cpir16,1 \n\t" "breqwait_spm3 \n\t" "ldir16,0x01\n\t"//Load r0,r1 into FLASH page buffer "sts%0,r16\n\t" "spm\n\t" "incr17\n\t"//page_word_count++ "cpi r17,%1 \n\t" "brlosame_page\n\t"//Still same page in FLASH "write_page:\n\t" "clrr17\n\t"//New page, write current one first "wait_spm4:\n\t" "ldsr16,%0\n\t"//Wait for previous spm to complete "andir16,1 \n\t" "cpir16,1 \n\t" "breqwait_spm4 \n\t"#ifdef __AVR_ATmega163__ "andir30,0x80\n\t"// m163 requires Z6:Z1 to be zero during page write#endif "ldir16,0x05\n\t"//Write page pointed to by Z "sts%0,r16\n\t" "spm\n\t"#ifdef __AVR_ATmega163__ ".word 0xFFFF\n\t" "nop\n\t" "orir30,0x7E\n\t"// recover Z6:Z1 state after page write (had to be zero during write)#endif "wait_spm5:\n\t" "ldsr16,%0\n\t"//Wait for previous spm to complete "andir16,1 \n\t" "cpir16,1 \n\t" "breqwait_spm5 \n\t" "ldir16,0x11\n\t"//Re-enable RWW section "sts%0,r16\n\t" "spm\n\t" #ifdef __AVR_ATmega163__ ".word 0xFFFF\n\t" "nop\n\t"#endif "same_page:\n\t" "adiwr30,2\n\t"//Next word in FLASH "sbiwr24,2\n\t"//length-2 "breqfinal_write\n\t"//Finished "rjmplength_loop\n\t" "final_write:\n\t" "cpir17,0\n\t" "breqblock_done\n\t" "adiwr24,2\n\t"//length+2, fool above check on length after short page write "rjmpwrite_page\n\t" "block_done:\n\t" "clr__zero_reg__\n\t"//restore zero register#if defined __AVR_ATmega168__ || __AVR_ATmega328P__ || __AVR_ATmega128__ || __AVR_ATmega1280__ || __AVR_ATmega1281__ : "=m" (SPMCSR) : "M" (PAGE_SIZE) : "r0","r16","r17","r24","r25","r28","r29","r30","r31"#else : "=m" (SPMCR) : "M" (PAGE_SIZE) : "r0","r16","r17","r24","r25","r28","r29","r30","r31"#endif );/* Should really add a wait for RWW section to be enabled, don't actually need it since we never *//* exit the bootloader without a power cycle anyhow */}putch(0x14);putch(0x10);} else {if (++error_count == MAX_ERROR_COUNT)app_start();}}/* Read memory block mode, length is big endian. */else if(ch=='t') {length.byte[1] = getch();length.byte[0] = getch();#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)if (address.word>0x7FFF) flags.rampz = 1;// No go with m256, FIXMEelse flags.rampz = 0;#endifaddress.word = address.word << 1; // address * 2 -> byte locationif (getch() == 'E') flags.eeprom = 1;else flags.eeprom = 0;if (getch() == ' ') { // Command terminatorputch(0x14);for (w=0;w < length.word;w++) { // Can handle odd and even lengths okayif (flags.eeprom) { // Byte access EEPROM read#if defined(__AVR_ATmega168__) || defined(__AVR_ATmega328P__)while(EECR & (1<<EEPE));EEAR = (uint16_t)(void *)address.word;EECR |= (1<<EERE);putch(EEDR);#elseputch(eeprom_read_byte((void *)address.word));#endifaddress.word++;}else {if (!flags.rampz) putch(pgm_read_byte_near(address.word));#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)else putch(pgm_read_byte_far(address.word + 0x10000));// Hmmmm, yuck FIXME when m256 arrvies#endifaddress.word++;}}putch(0x10);}}/* Get device signature bytes */else if(ch=='u') {if (getch() == ' ') {putch(0x14);putch(SIG1);putch(SIG2);putch(SIG3);putch(0x10);} else {if (++error_count == MAX_ERROR_COUNT)app_start();}}/* Read oscillator calibration byte */else if(ch=='v') {byte_response(0x00);}#if defined MONITOR /* here come the extended monitor commands by Erik Lins *//* check for three times exclamation mark pressed */else if(ch=='!') {ch = getch();if(ch=='!') {ch = getch();if(ch=='!') {PGM_P welcome = "";#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)uint16_t extaddr;#endifuint8_t addrl, addrh;#ifdef CRUMB128welcome = "ATmegaBOOT / Crumb128 - (C) J.P.Kyle, E.Lins - 050815\n\r";#elif defined PROBOMEGA128welcome = "ATmegaBOOT / PROBOmega128 - (C) J.P.Kyle, E.Lins - 050815\n\r";#elif defined SAVVY128welcome = "ATmegaBOOT / Savvy128 - (C) J.P.Kyle, E.Lins - 050815\n\r";#elif defined __AVR_ATmega1280__ welcome = "ATmegaBOOT / Arduino Mega - (C) Arduino LLC - 090930\n\r";#endif/* turn on LED */LED_DDR |= _BV(LED);LED_PORT &= ~_BV(LED);/* print a welcome message and command overview */for(i=0; welcome[i] != '\0'; ++i) {putch(welcome[i]);}/* test for valid commands */for(;;) {putch('\n');putch('\r');putch(':');putch(' ');ch = getch();putch(ch);/* toggle LED */if(ch == 't') {if(bit_is_set(LED_PIN,LED)) {LED_PORT &= ~_BV(LED);putch('1');} else {LED_PORT |= _BV(LED);putch('0');}} /* read byte from address */else if(ch == 'r') {ch = getch(); putch(ch);addrh = gethex();addrl = gethex();putch('=');ch = *(uint8_t *)((addrh << 8) + addrl);puthex(ch);}/* write a byte to address */else if(ch == 'w') {ch = getch(); putch(ch);addrh = gethex();addrl = gethex();ch = getch(); putch(ch);ch = gethex();*(uint8_t *)((addrh << 8) + addrl) = ch;}/* read from uart and echo back */else if(ch == 'u') {for(;;) {putch(getch());}}#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)/* external bus loop */else if(ch == 'b') {putch('b');putch('u');putch('s');MCUCR = 0x80;XMCRA = 0;XMCRB = 0;extaddr = 0x1100;for(;;) {ch = *(volatile uint8_t *)extaddr;if(++extaddr == 0) {extaddr = 0x1100;}}}#endifelse if(ch == 'j') {app_start();}} /* end of monitor functions */}}}/* end of monitor */#endifelse if (++error_count == MAX_ERROR_COUNT) {app_start();}} /* end of forever loop */}char gethexnib(void) {char a;a = getch(); putch(a);if(a >= 'a') {return (a - 'a' + 0x0a);} else if(a >= '0') {return(a - '0');}return a;}char gethex(void) {return (gethexnib() << 4) + gethexnib();}void puthex(char ch) {char ah;ah = ch >> 4;if(ah >= 0x0a) {ah = ah - 0x0a + 'a';} else {ah += '0';}ch &= 0x0f;if(ch >= 0x0a) {ch = ch - 0x0a + 'a';} else {ch += '0';}putch(ah);putch(ch);}void putch(char ch){#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)if(bootuart == 1) {while (!(UCSR0A & _BV(UDRE0)));UDR0 = ch;}else if (bootuart == 2) {while (!(UCSR1A & _BV(UDRE1)));UDR1 = ch;}#elif defined(__AVR_ATmega168__) || defined(__AVR_ATmega328P__)while (!(UCSR0A & _BV(UDRE0)));UDR0 = ch;#else/* m8,16,32,169,8515,8535,163 */while (!(UCSRA & _BV(UDRE)));UDR = ch;#endif}char getch(void){#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)uint32_t count = 0;if(bootuart == 1) {while(!(UCSR0A & _BV(RXC0))) {/* 20060803 DojoCorp:: Addon coming from the previous Bootloader*/ /* HACKME:: here is a good place to count times*/count++;if (count > MAX_TIME_COUNT)app_start();}return UDR0;}else if(bootuart == 2) {while(!(UCSR1A & _BV(RXC1))) {/* 20060803 DojoCorp:: Addon coming from the previous Bootloader*/ /* HACKME:: here is a good place to count times*/count++;if (count > MAX_TIME_COUNT)app_start();}return UDR1;}return 0;#elif defined(__AVR_ATmega168__) || defined(__AVR_ATmega328P__)uint32_t count = 0;while(!(UCSR0A & _BV(RXC0))){/* 20060803 DojoCorp:: Addon coming from the previous Bootloader*/ /* HACKME:: here is a good place to count times*/count++;if (count > MAX_TIME_COUNT)app_start();}return UDR0;#else/* m8,16,32,169,8515,8535,163 */uint32_t count = 0;while(!(UCSRA & _BV(RXC))){/* 20060803 DojoCorp:: Addon coming from the previous Bootloader*/ /* HACKME:: here is a good place to count times*/count++;if (count > MAX_TIME_COUNT)app_start();}return UDR;#endif}void getNch(uint8_t count){while(count--) {#if defined(__AVR_ATmega128__) || defined(__AVR_ATmega1280__)if(bootuart == 1) {while(!(UCSR0A & _BV(RXC0)));UDR0;} else if(bootuart == 2) {while(!(UCSR1A & _BV(RXC1)));UDR1;}#elif defined(__AVR_ATmega168__) || defined(__AVR_ATmega328P__)getch();#else/* m8,16,32,169,8515,8535,163 *//* 20060803 DojoCorp:: Addon coming from the previous Bootloader*/ //while(!(UCSRA & _BV(RXC)));//UDR;getch(); // need to handle time out#endif}}void byte_response(uint8_t val){if (getch() == ' ') {putch(0x14);putch(val);putch(0x10);} else {if (++error_count == MAX_ERROR_COUNT)app_start();}}void nothing_response(void){if (getch() == ' ') {putch(0x14);putch(0x10);} else {if (++error_count == MAX_ERROR_COUNT)app_start();}}void flash_led(uint8_t count){while (count--) {LED_PORT |= _BV(LED);_delay_ms(100);LED_PORT &= ~_BV(LED);_delay_ms(100);}}/* end of file ATmegaBOOT.c */ 0 0
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