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optiboot_flash.c
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#define FUNC_READ 1
#define FUNC_WRITE 1
/**********************************************************/
/* MCUdude's Optiboot bootloader for Arduino */
/* */
/* Based on majekw's Optiboot fork. */
/* http://github.com/majekw/optiboot */
/* */
/* It is the intent that changes not relevant to the */
/* Arduino production envionment get moved from the */
/* optiboot project to the arduino project in "lumps." */
/* */
/* Heavily optimised bootloader that is faster and */
/* smaller than the Arduino standard bootloader */
/* */
/* Enhancements: */
/* Fits in 512 bytes, saving 1.5K of code space */
/* Higher baud rate speeds up programming */
/* Written almost entirely in C */
/* Customisable timeout with accurate timeconstant */
/* Optional virtual UART. No hardware UART required. */
/* Optional virtual boot partition for devices without. */
/* Supports "write to flash" in application! */
/* */
/* What you lose: */
/* Implements a skeleton STK500 protocol which is */
/* missing several features including EEPROM */
/* programming and non-page-aligned writes */
/* High baud rate breaks compatibility with standard */
/* Arduino flash settings */
/* */
/* */
/* Supported microcontrollers: */
/* See https://github.com/MCUdude/optiboot_flash */
/* */
/* Assumptions: */
/* The code makes several assumptions that reduce the */
/* code size. They are all true after a hardware reset, */
/* but may not be true if the bootloader is called by */
/* other means or on other hardware. */
/* No interrupts can occur */
/* UART and Timer 1 are set to their reset state */
/* SP points to RAMEND */
/* */
/* Code builds on code, libraries and optimisations from: */
/* stk500boot.c by Jason P. Kyle */
/* Arduino bootloader http://arduino.cc */
/* Spiff's 1K bootloader http://spiffie.org/know/arduino_1k_bootloader/bootloader.shtml */
/* avr-libc project http://nongnu.org/avr-libc */
/* Adaboot http://www.ladyada.net/library/arduino/bootloader.html */
/* AVR305 Atmel Application Note */
/* */
/* */
/* Copyright 2013-2015 by Bill Westfield. */
/* Copyright 2010 by Peter Knight. */
/* */
/* 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 */
/* */
/**********************************************************/
/**********************************************************/
/* */
/* Optional defines: */
/* */
/**********************************************************/
/* */
/* */
/* BAUD_RATE: */
/* Set bootloader baud rate. */
/* */
/* SOFT_UART: */
/* Use AVR305 soft-UART instead of hardware UART. */
/* */
/* LED_START_FLASHES: */
/* Number of LED flashes on bootup. */
/* */
/* LED_DATA_FLASH: */
/* Flash LED when transferring data. For boards without */
/* TX or RX LEDs, or for people who like blinky lights. */
/* */
/* UART: */
/* UART number (0..n) for devices with more than */
/* one hardware uart (644P, 1284P, etc) */
/* */
/* TIMEOUT_MS: */
/* Bootloader timeout period, in milliseconds. */
/* 500,1000,2000,4000,8000 supported. */
/* */
/* SUPPORT_EEPROM: */
/* Support reading and writing from EEPROM. This is not */
/* used by Arduino, so off by default. */
/* */
/* COPY_FLASH_PAGES: */
/* Adds function to copy flash pages. The function is */
/* intended to be called by the application. */
/* */
/**********************************************************/
/**********************************************************/
/* Version Numbers! */
/* */
/* Arduino Optiboot now includes this Version number in */
/* the source and object code. */
/* */
/* Version 3 was released as zip from the optiboot */
/* repository and was distributed with Arduino 0022. */
/* Version 4 starts with the arduino repository commit */
/* that brought the arduino repository up-to-date with */
/* the optiboot source tree changes since v3. */
/* Version 5 was created at the time of the new Makefile */
/* structure (Mar, 2013), even though no binaries changed*/
/* It would be good if versions implemented outside the */
/* official repository used an out-of-seqeunce version */
/* number (like 104.6 if based on based on 4.5) to */
/* prevent collisions. */
/* */
/**********************************************************/
/**********************************************************/
/* Edit History: */
/* */
/* July 2018 */
/* 7.0 WestfW (with much input from others) */
/* Fix MCUSR treatement as per much discussion, */
/* Patches by MarkG55, majekw. */
/* Preserve value for the application, */
/* as much as possible. */
/* See https://github.com/Optiboot/optiboot/issues/97 */
/* Optimize a bit by implementing a union for the */
/* various 16bit address values used (based on */
/* observation by "aweatherguy", but different.) */
/* Slightly optimize math in VIRTUAL_BOOT code */
/* Add some virboot targets, fix some fuses. */
/* Implement LED_START_ON; less code than flashes */
/* */
/* Aug 2014 */
/* 6.2 WestfW: make size of length variables dependent */
/* on the SPM_PAGESIZE. This saves space */
/* on the chips where it's most important. */
/* 6.1 WestfW: Fix OPTIBOOT_CUSTOMVER (send it!) */
/* Make no-wait mod less picky about */
/* skipping the bootloader. */
/* Remove some dead code */
/* */
/* Jun 2014 */
/* 6.0 WestfW: Modularize memory read/write functions */
/* Remove serial/flash overlap */
/* (and all references to NRWWSTART/etc) */
/* Correctly handle pagesize > 255bytes */
/* Add EEPROM support in BIGBOOT (1284) */
/* EEPROM write on small chips now causes err */
/* Split Makefile into smaller pieces */
/* Add Wicked devices Wildfire */
/* Move UART=n conditionals into pin_defs.h */
/* Remove LUDICOUS_SPEED option */
/* Replace inline assembler for .version */
/* and add OPTIBOOT_CUSTOMVER for user code */
/* Fix LED value for Bobuino (Makefile) */
/* Make all functions explicitly inline or */
/* noinline, so we fit when using gcc4.8 */
/* Change optimization options for gcc4.8 */
/* Make ENV=arduino work in 1.5.x trees. */
/* */
/* May 2014 */
/* 5.0 WestfW: Add support for 1Mbps UART */
/* */
/* Mar 2013 */
/* 5.0 WestfW: Major Makefile restructuring. */
/* See Makefile and pin_defs.h */
/* (no binary changes) */
/* 4.6 WestfW/Pito: Add ATmega32 support */
/* 4.6 WestfW/radoni: Don't set LED_PIN as an output if */
/* not used. (LED_START_FLASHES = 0) */
/* */
/* Jan 2013 */
/* 4.6 WestfW/dkinzer: use autoincrement lpm for read */
/* 4.6 WestfW/dkinzer: pass reset cause to app in R2 */
/* */
/* Mar 2012 */
/* 4.5 WestfW: add infrastructure for non-zero UARTS. */
/* 4.5 WestfW: fix SIGNATURE_2 for m644 (bad in avr-libc) */
/* */
/* Jan 2012: */
/* 4.5 WestfW: fix NRWW value for m1284. */
/* 4.4 WestfW: use attribute OS_main instead of naked for */
/* main(). This allows optimizations that we */
/* count on, which are prohibited in naked */
/* functions due to PR42240. (keeps us less */
/* than 512 bytes when compiler is gcc4.5 */
/* (code from 4.3.2 remains the same.) */
/* 4.4 WestfW and Maniacbug: Add m1284 support. This */
/* does not change the 328 binary, so the */
/* version number didn't change either. (?) */
/* */
/* June 2011: */
/* 4.4 WestfW: remove automatic soft_uart detect (didn't */
/* know what it was doing or why.) Added a */
/* check of the calculated BRG value instead. */
/* Version stays 4.4; existing binaries are */
/* not changed. */
/* 4.4 WestfW: add initialization of address to keep */
/* the compiler happy. Change SC'ed targets. */
/* Return the SW version via READ PARAM */
/* 4.3 WestfW: catch framing errors in getch(), so that */
/* AVRISP works without HW kludges. */
/* http://code.google.com/p/arduino/issues/detail?id=368n*/
/* 4.2 WestfW: reduce code size, fix timeouts, change */
/* verifySpace to use WDT instead of appstart */
/* 4.1 WestfW: put version number in binary. */
/**********************************************************/
#define OPTIBOOT_MAJVER 7
#define OPTIBOOT_MINVER 0
/*
* OPTIBOOT_CUSTOMVER should be defined (by the makefile) for custom edits
* of optiboot. That way you don't wind up with very different code that
* matches the version number of a "released" optiboot.
*/
#if !defined(OPTIBOOT_CUSTOMVER)
#define OPTIBOOT_CUSTOMVER 0
#endif
unsigned const int __attribute__((section(".version")))
optiboot_version = 256*(OPTIBOOT_MAJVER + OPTIBOOT_CUSTOMVER) + OPTIBOOT_MINVER;
#include <inttypes.h>
#include <avr/io.h>
#include <avr/pgmspace.h>
#include <avr/eeprom.h>
#include "boot.h"
#include "pin_defs.h"
#include "stk500.h"
/*
* optiboot uses several "address" variables that are sometimes byte pointers,
* sometimes word pointers. sometimes 16bit quantities, and sometimes built
* up from 8bit input characters. avr-gcc is not great at optimizing the
* assembly of larger words from bytes, but we can use the usual union to
* do this manually. Expanding it a little, we can also get rid of casts.
*/
typedef union
{
uint8_t *bptr;
uint16_t *wptr;
uint16_t word;
uint8_t bytes[2];
} addr16_t;
#ifndef LED_START_FLASHES
#define LED_START_FLASHES 0
#endif
/* set the UART baud rate defaults */
#ifndef BAUD_RATE
#if F_CPU >= 8000000L
#define BAUD_RATE 115200L // Highest rate Avrdude win32 will support
#elif F_CPU >= 1000000L
#define BAUD_RATE 9600L // 19200 also supported, but with significant error
#elif F_CPU >= 128000L
#define BAUD_RATE 4800L // Good for 128kHz internal RC
#else
#define BAUD_RATE 1200L // Good even at 32768Hz
#endif
#endif
#ifndef UART
#define UART 0
#endif
#ifdef SINGLESPEED // U2X = 0
/* Single speed option */
#define BAUD_SETTING (( (F_CPU + BAUD_RATE * 8L) / ((BAUD_RATE * 16L))) - 1 )
#define BAUD_ACTUAL (F_CPU/(16 * ((BAUD_SETTING)+1)))
#else
/* Normal U2X usage */
#define BAUD_SETTING (( (F_CPU + BAUD_RATE * 4L) / ((BAUD_RATE * 8L))) - 1 )
#define BAUD_ACTUAL (F_CPU/(8 * ((BAUD_SETTING)+1)))
#endif
#if BAUD_ACTUAL <= BAUD_RATE
#define BAUD_ERROR (( 100*(BAUD_RATE - BAUD_ACTUAL) ) / BAUD_RATE)
#if BAUD_ERROR >= 5
#error BAUD_RATE error greater than -5%
#elif BAUD_ERROR >= 2
#warning BAUD_RATE error greater than -2%
#endif
#else
#define BAUD_ERROR (( 100*(BAUD_ACTUAL - BAUD_RATE) ) / BAUD_RATE)
#if BAUD_ERROR >= 5
#error BAUD_RATE error greater than 5%
#elif BAUD_ERROR >= 2
#warning BAUD_RATE error greater than 2%
#endif
#endif
#if BAUD_SETTING > 250
#error Unachievable baud rate (too slow) BAUD_RATE
#endif // baud rate slow check
#if (BAUD_SETTING - 1) < 3
#if BAUD_ERROR != 0 // permit high bitrates (ie 1Mbps@16MHz) if error is zero
#error Unachievable baud rate (too fast) BAUD_RATE
#endif
#endif // baud rate fast check
/* Watchdog settings */
#define WATCHDOG_OFF (0)
#define WATCHDOG_16MS (_BV(WDE))
#define WATCHDOG_32MS (_BV(WDP0) | _BV(WDE))
#define WATCHDOG_64MS (_BV(WDP1) | _BV(WDE))
#define WATCHDOG_125MS (_BV(WDP1) | _BV(WDP0) | _BV(WDE))
#define WATCHDOG_250MS (_BV(WDP2) | _BV(WDE))
#define WATCHDOG_500MS (_BV(WDP2) | _BV(WDP0) | _BV(WDE))
#define WATCHDOG_1S (_BV(WDP2) | _BV(WDP1) | _BV(WDE))
#define WATCHDOG_2S (_BV(WDP2) | _BV(WDP1) | _BV(WDP0) | _BV(WDE))
#ifndef __AVR_ATmega8__
#define WATCHDOG_4S (_BV(WDP3) | _BV(WDE))
#define WATCHDOG_8S (_BV(WDP3) | _BV(WDP0) | _BV(WDE))
#endif
/*
* We can never load flash with more than 1 page at a time, so we can save
* some code space on parts with smaller pagesize by using a smaller int.
*/
#if SPM_PAGESIZE > 255
typedef uint16_t pagelen_t ;
#define GETLENGTH(len) len = getch()<<8; len |= getch()
#else
typedef uint8_t pagelen_t;
#define GETLENGTH(len) (void) getch() /* skip high byte */; len = getch()
#endif
/* Function Prototypes
* The main() function is in init9, which removes the interrupt vector table
* we don't need. It is also 'OS_main', which means the compiler does not
* generate any entry or exit code itself (but unlike 'naked', it doesn't
* supress some compile-time options we want.)
*/
void pre_main(void) __attribute__ ((naked)) __attribute__ ((section (".init8")));
int main(void) __attribute__ ((OS_main)) __attribute__ ((section (".init9")));
void __attribute__((noinline)) putch(char);
uint8_t __attribute__((noinline)) getch(void);
void __attribute__((noinline)) verifySpace();
void __attribute__((noinline)) watchdogConfig(uint8_t x);
static void getNch(uint8_t);
#if LED_START_FLASHES > 0
static inline void flash_led(uint8_t);
#endif
static inline void watchdogReset();
static inline void writebuffer(int8_t memtype, addr16_t mybuff,
addr16_t address, pagelen_t len);
static inline void read_mem(uint8_t memtype,
addr16_t, pagelen_t len);
static void __attribute__((noinline)) do_spm(uint16_t address, uint8_t command, uint16_t data);
#ifdef SOFT_UART
void uartDelay() __attribute__ ((naked));
#endif
//void appStart(uint8_t rstFlags) __attribute__ ((naked));
/*
* RAMSTART should be self-explanatory. It's bigger on parts with a
* lot of peripheral registers. Let 0x100 be the default
* Note that RAMSTART (for optiboot) need not be exactly at the start of RAM.
*/
#if !defined(RAMSTART) // newer versions of gcc avr-libc define RAMSTART
#define RAMSTART 0x100
#if defined (__AVR_ATmega644P__)
// correct for a bug in avr-libc
#undef SIGNATURE_2
#define SIGNATURE_2 0x0A
#elif defined(__AVR_ATmega1280__) || defined(__AVR_ATmega1281__) || defined(__AVR_ATmega2560__) || defined(__AVR_ATmega2561__)
#undef RAMSTART
#define RAMSTART (0x200)
#endif
#endif
/* C zero initialises all global variables. However, that requires */
/* These definitions are NOT zero initialised, but that doesn't matter */
/* This allows us to drop the zero init code, saving us memory */
static addr16_t buff = {(uint8_t *)(RAMSTART)};
/* Virtual boot partition support */
#ifdef VIRTUAL_BOOT_PARTITION
#define rstVect0_sav (*(uint8_t*)(RAMSTART+SPM_PAGESIZE*2+4))
#define rstVect1_sav (*(uint8_t*)(RAMSTART+SPM_PAGESIZE*2+5))
#define saveVect0_sav (*(uint8_t*)(RAMSTART+SPM_PAGESIZE*2+6))
#define saveVect1_sav (*(uint8_t*)(RAMSTART+SPM_PAGESIZE*2+7))
// Vector to save original reset jump:
// SPM Ready is least probably used, so it's default
// if not, use old way WDT_vect_num,
// or simply set custom save_vect_num in Makefile using vector name
// or even raw number.
#if !defined (save_vect_num)
#if defined (SPM_RDY_vect_num)
#define save_vect_num (SPM_RDY_vect_num)
#elif defined (SPM_READY_vect_num)
#define save_vect_num (SPM_READY_vect_num)
#elif defined (WDT_vect_num)
#define save_vect_num (WDT_vect_num)
#else
#error Cant find SPM or WDT interrupt vector for this CPU
#endif
#endif //save_vect_num
// check if it's on the same page (code assumes that)
#if (SPM_PAGESIZE <= save_vect_num)
#error Save vector not in the same page as reset!
#endif
#if FLASHEND > 8192
// AVRs with more than 8k of flash have 4-byte vectors, and use jmp.
// We save only 16 bits of address, so devices with more than 128KB
// may behave wrong for upper part of address space.
#define rstVect0 2
#define rstVect1 3
#define saveVect0 (save_vect_num*4+2)
#define saveVect1 (save_vect_num*4+3)
#define appstart_vec (save_vect_num*2)
#else
// AVRs with up to 8k of flash have 2-byte vectors, and use rjmp.
#define rstVect0 0
#define rstVect1 1
#define saveVect0 (save_vect_num*2)
#define saveVect1 (save_vect_num*2+1)
#define appstart_vec (save_vect_num)
#endif
#else
#define appstart_vec (0)
#endif // VIRTUAL_BOOT_PARTITION
/* everything that needs to run VERY early */
void pre_main(void) {
// Allow convenient way of calling do_spm function - jump table,
// so entry to this function will always be here, indepedent of compilation,
// features etc
asm volatile (
" rjmp 1f\n"
" rjmp do_spm\n"
#ifdef COPY_FLASH_PAGES
" rjmp copy_flash_pages\n"
#endif
"1:\n"
);
}
/* main program starts here */
int main(void) {
uint8_t ch;
/*
* Making these local and in registers prevents the need for initializing
* them, and also saves space because code no longer stores to memory.
* (initializing address keeps the compiler happy, but isn't really
* necessary, and uses 4 bytes of flash.)
*/
register addr16_t address;
register pagelen_t length;
// After the zero init loop, this is the first code to run.
//
// This code makes the following assumptions:
// No interrupts will execute
// SP points to RAMEND
// r1 contains zero
//
// If not, uncomment the following instructions:
// cli();
asm volatile ("clr __zero_reg__");
#if defined(__AVR_ATmega8__) || defined(__AVR_ATmega8515__) || defined(__AVR_ATmega8535__) \
|| defined (__AVR_ATmega16__) || defined (__AVR_ATmega32__) || defined (__AVR_ATmega64__) \
|| defined (__AVR_ATmega128__) || defined (__AVR_ATmega162__) || defined (__AVR_AT90CAN32__) \
|| defined (__AVR_AT90CAN64__) || defined (__AVR_AT90CAN128__)
SP=RAMEND; // This is done by hardware reset
#endif
/*
* Protect as much from MCUSR as possible for application
* and still skip bootloader if not necessary
*
* Code by MarkG55
* see discusion in https://github.com/Optiboot/optiboot/issues/97
*/
// Fix ATmega128 avr-libc bug
#if defined(__AVR_ATmega128__)
ch = MCUCSR;
#else
ch = MCUSR;
#endif
// This is necessary on targets that where the CLKPR has been set in user application
#if defined(CLKPR) && F_CPU != 1000000L
CLKPR = 0x80; // Enable the clock prescaler
CLKPR = 0x00; // Set prescaler to 1
#endif
// Skip all logic and run bootloader if MCUSR is cleared (application request)
if (ch != 0) {
/*
* To run the boot loader, External Reset Flag must be set.
* If not, we could make shortcut and jump directly to application code.
* Also WDRF set with EXTRF is a result of Optiboot timeout, so we
* shouldn't run bootloader in loop :-) That's why:
* 1. application is running if WDRF is cleared
* 2. we clear WDRF if it's set with EXTRF to avoid loops
* One problematic scenario: broken application code sets watchdog timer
* without clearing MCUSR before and triggers it quickly. But it's
* recoverable by power-on with pushed reset button.
*/
if ((ch & (_BV(WDRF) | _BV(EXTRF))) != _BV(EXTRF)) {
if (ch & _BV(EXTRF)) {
/*
* Clear WDRF because it was most probably set by wdr in bootloader.
* It's also needed to avoid loop by broken application which could
* prevent entering bootloader.
* '&' operation is skipped to spare few bytes as bits in MCUSR
* can only be cleared.
*/
// Fix ATmega128 avr-libc bug
#if defined(__AVR_ATmega128__)
MCUCSR = ~(_BV(WDRF));
#else
MCUSR = ~(_BV(WDRF));
#endif
}
/*
* save the reset flags in the designated register
* This can be saved in a main program by putting code in .init0 (which
* executes before normal c init code) to save R2 to a global variable.
*/
__asm__ __volatile__ ("mov r2, %0\n" :: "r" (ch));
// Turn off watchdog
watchdogConfig(WATCHDOG_OFF);
// Note that appstart_vec is defined so that this works with either
// real or virtual boot partitions.
__asm__ __volatile__ (
// Jump to 'save' or RST vector
#ifdef VIRTUAL_BOOT_PARTITION
// full code version for virtual boot partition
"ldi r30,%[rstvec]\n"
"clr r31\n"
"ijmp\n"::[rstvec] "M"(appstart_vec)
#else
#ifdef RAMPZ
// use absolute jump for devices with lot of flash
"jmp 0\n"::
#else
// use rjmp to go around end of flash to address 0
// it uses fact that optiboot_version constant is 2 bytes before end of flash
"rjmp optiboot_version+2\n"
#endif //RAMPZ
#endif //VIRTUAL_BOOT_PARTITION
);
}
}
#if LED_START_FLASHES > 0
// Set up Timer 1 for timeout counter
TCCR1B = _BV(CS12) | _BV(CS10); // div 1024
#endif
#ifndef SOFT_UART
// ATmega8/8515/8535/16/32 only has one UART port
#if defined(__AVR_ATmega8__) || defined (__AVR_ATmega8515__) || defined (__AVR_ATmega8535__) \
|| defined (__AVR_ATmega16__) || defined (__AVR_ATmega32__)
#ifndef SINGLESPEED
UCSRA = _BV(U2X); // Double speed mode USART
#endif
UCSRB = _BV(RXEN) | _BV(TXEN); // enable Rx & Tx
UCSRC = _BV(URSEL) | _BV(UCSZ1) | _BV(UCSZ0); // config USART; 8N1
UBRRL = (uint8_t)BAUD_SETTING;
#else
#ifndef SINGLESPEED
UART_SRA = _BV(U2X0); // Double speed mode USART0
#endif
UART_SRB = _BV(RXEN0) | _BV(TXEN0);
UART_SRL = (uint8_t)BAUD_SETTING;
#if defined(__AVR_ATmega162__)
UART_SRC = _BV(URSEL0) | _BV(UCSZ00) | _BV(UCSZ01);
#else
UART_SRC = _BV(UCSZ00) | _BV(UCSZ01);
#endif
#endif
#endif
// Set up watchdog to trigger after 1s
watchdogConfig(WATCHDOG_1S);
#if (LED_START_FLASHES > 0) || defined(LED_DATA_FLASH) || defined(LED_START_ON)
/* Set LED pin as output */
LED_DDR |= _BV(LED);
#endif
#ifdef SOFT_UART
/* Set TX pin as output */
UART_DDR |= _BV(UART_TX_BIT);
#endif
#if LED_START_FLASHES > 0
/* Flash onboard LED to signal entering of bootloader */
flash_led(LED_START_FLASHES * 2);
#elif defined(LED_START_ON)
/* Turn on LED to indicate starting bootloader (less code!) */
LED_PORT |= _BV(LED);
#endif
/* Forever loop: exits by causing WDT reset */
for (;;) {
/* get character from UART */
ch = getch();
if(ch == STK_GET_PARAMETER) {
unsigned char which = getch();
verifySpace();
/*
* Send optiboot version as "SW version"
* Note that the references to memory are optimized away.
*/
if (which == STK_SW_MINOR) {
putch(optiboot_version & 0xFF);
} else if (which == STK_SW_MAJOR) {
putch(optiboot_version >> 8);
} else {
/*
* GET PARAMETER returns a generic 0x03 reply for
* other parameters - enough to keep Avrdude happy
*/
putch(0x03);
}
}
else if(ch == STK_SET_DEVICE) {
// SET DEVICE is ignored
getNch(20);
}
else if(ch == STK_SET_DEVICE_EXT) {
// SET DEVICE EXT is ignored
getNch(5);
}
else if(ch == STK_LOAD_ADDRESS) {
// LOAD ADDRESS
address.bytes[0] = getch();
address.bytes[1] = getch();
#ifdef RAMPZ
// Transfer top bit to LSB in RAMPZ
if (address.bytes[1] & 0x80) {
RAMPZ |= 0x01;
}
else {
RAMPZ &= 0xFE;
}
#endif
address.word *= 2; // Convert from word address to byte address
verifySpace();
}
else if(ch == STK_UNIVERSAL) {
#ifdef RAMPZ
// LOAD_EXTENDED_ADDRESS is needed in STK_UNIVERSAL for addressing more than 128kB
if ( AVR_OP_LOAD_EXT_ADDR == getch() ) {
// get address
getch(); // get '0'
RAMPZ = (RAMPZ & 0x01) | ((getch() << 1) & 0xff); // get address and put it in RAMPZ
getNch(1); // get last '0'
// response
putch(0x00);
}
else {
// everything else is ignored
getNch(3);
putch(0x00);
}
#else
// UNIVERSAL command is ignored
getNch(4);
putch(0x00);
#endif
}
/* Write memory, length is big endian and is in bytes */
else if(ch == STK_PROG_PAGE) {
// PROGRAM PAGE - we support flash programming only, not EEPROM
uint8_t desttype;
uint8_t *bufPtr;
pagelen_t savelength;
GETLENGTH(length);
savelength = length;
desttype = getch();
// read a page worth of contents
bufPtr = buff.bptr;
do *bufPtr++ = getch();
while (--length);
// Read command terminator, start reply
verifySpace();
#ifdef VIRTUAL_BOOT_PARTITION
#if FLASHEND > 8192
/*
* AVR with 4-byte ISR Vectors and "jmp"
* WARNING: this works only up to 128KB flash!
*/
if (address.word == 0) {
// This is the reset vector page. We need to live-patch the
// code so the bootloader runs first.
//
// Save jmp targets (for "Verify")
rstVect0_sav = buff.bptr[rstVect0];
rstVect1_sav = buff.bptr[rstVect1];
saveVect0_sav = buff.bptr[saveVect0];
saveVect1_sav = buff.bptr[saveVect1];
// Move RESET jmp target to 'save' vector
buff.bptr[saveVect0] = rstVect0_sav;
buff.bptr[saveVect1] = rstVect1_sav;
// Add jump to bootloader at RESET vector
// WARNING: this works as long as 'main' is in first section
buff.bptr[rstVect0] = ((uint16_t)main) & 0xFF;
buff.bptr[rstVect1] = ((uint16_t)main) >> 8;
}
#else
/*
* AVR with 2-byte ISR Vectors and rjmp
*/
if (address.word == rstVect0) {
// This is the reset vector page. We need to live-patch
// the code so the bootloader runs first.
//
// Move RESET vector to 'save' vector
// Save jmp targets (for "Verify")
rstVect0_sav = buff.bptr[rstVect0];
rstVect1_sav = buff.bptr[rstVect1];
saveVect0_sav = buff.bptr[saveVect0];
saveVect1_sav = buff.bptr[saveVect1];
// Instruction is a relative jump (rjmp), so recalculate.
// an RJMP instruction is 0b1100xxxx xxxxxxxx, so we should be able to
// do math on the offsets without masking it off first.
addr16_t vect;
vect.bytes[0] = rstVect0_sav;
vect.bytes[1] = rstVect1_sav;
vect.word = (vect.word-save_vect_num); //substract 'save' interrupt position
// Move RESET jmp target to 'save' vector
buff[saveVect0] = vect & 0xff;
buff[saveVect1] = (vect >> 8) | 0xc0; //
// Add rjump to bootloader at RESET vector
vect.word = ((uint16_t)main); // (main) is always <= 0x0FFF; no masking needed.
buff.bptr[0] = vect.bytes[0]; // rjmp 0x1c00 instruction
buff.bptr[1] = vect.bytes[1] | 0xC0; // make an "rjmp"
}
#endif // FLASHEND
#endif // VBP
writebuffer(desttype, buff, address, savelength);
}
/* Read memory block mode, length is big endian. */
else if(ch == STK_READ_PAGE) {
uint8_t desttype;
GETLENGTH(length);
desttype = getch();
verifySpace();
read_mem(desttype, address, length);
}
/* Get device signature bytes */
else if(ch == STK_READ_SIGN) {
// READ SIGN - return what Avrdude wants to hear
verifySpace();
putch(SIGNATURE_0);
putch(SIGNATURE_1);
putch(SIGNATURE_2);
}
else if (ch == STK_LEAVE_PROGMODE) { /* 'Q' */
// Adaboot no-wait mod
watchdogConfig(WATCHDOG_16MS);
verifySpace();
}
else {
// This covers the response to commands like STK_ENTER_PROGMODE
verifySpace();
}
putch(STK_OK);
}
}
void putch(char ch) {
#ifndef SOFT_UART
while (!(UART_SRA & _BV(UDRE0)));
UART_UDR = ch;
#else
__asm__ __volatile__ (
" com %[ch]\n" // ones complement, carry set
" sec\n"
"1: brcc 2f\n"
" cbi %[uartPort],%[uartBit]\n"
" rjmp 3f\n"
"2: sbi %[uartPort],%[uartBit]\n"
" nop\n"
"3: rcall uartDelay\n"
" rcall uartDelay\n"
" lsr %[ch]\n"
" dec %[bitcnt]\n"
" brne 1b\n"
:
:
[bitcnt] "d" (10),
[ch] "r" (ch),
[uartPort] "I" (_SFR_IO_ADDR(UART_PORT)),
[uartBit] "I" (UART_TX_BIT)
:
"r25"
);
#endif
}
uint8_t getch(void) {
uint8_t ch;
#ifdef LED_DATA_FLASH
#if defined(__AVR_ATmega8__) || defined(__AVR_ATmega8515__) || defined(__AVR_ATmega8535__) \
|| defined(__AVR_ATmega16__) || defined(__AVR_ATmega162__) || defined(__AVR_ATmega32__) \
|| defined(__AVR_ATmega64__) || defined(__AVR_ATmega128__)
LED_PORT ^= _BV(LED);
#else
LED_PIN |= _BV(LED);
#endif
#endif
#ifdef SOFT_UART
watchdogReset();
__asm__ __volatile__ (
"1: sbic %[uartPin],%[uartBit]\n" // Wait for start edge
" rjmp 1b\n"
" rcall uartDelay\n" // Get to middle of start bit
"2: rcall uartDelay\n" // Wait 1 bit period
" rcall uartDelay\n" // Wait 1 bit period
" clc\n"
" sbic %[uartPin],%[uartBit]\n"
" sec\n"
" dec %[bitCnt]\n"
" breq 3f\n"
" ror %[ch]\n"
" rjmp 2b\n"
"3:\n"
:
[ch] "=r" (ch)
:
[bitCnt] "d" (9),
[uartPin] "I" (_SFR_IO_ADDR(UART_PIN)),
[uartBit] "I" (UART_RX_BIT)
:
"r25"
);
#else
while(!(UART_SRA & _BV(RXC0)))
;
if (!(UART_SRA & _BV(FE0))) {
/*
* A Framing Error indicates (probably) that something is talking
* to us at the wrong bit rate. Assume that this is because it
* expects to be talking to the application, and DON'T reset the
* watchdog. This should cause the bootloader to abort and run
* the application "soon", if it keeps happening. (Note that we
* don't care that an invalid char is returned...)
*/
watchdogReset();
}
ch = UART_UDR;
#endif
#ifdef LED_DATA_FLASH
#if defined(__AVR_ATmega8__) || defined(__AVR_ATmega8515__) || defined(__AVR_ATmega8535__) \
|| defined(__AVR_ATmega16__) || defined(__AVR_ATmega162__) ||defined(__AVR_ATmega32__) \
|| defined(__AVR_ATmega64__) || defined(__AVR_ATmega128__)
LED_PORT ^= _BV(LED);
#else
LED_PIN |= _BV(LED);
#endif
#endif
return ch;
}
#ifdef SOFT_UART
// AVR305 equation: #define UART_B_VALUE (((F_CPU/BAUD_RATE)-23)/6)
// Adding 3 to numerator simulates nearest rounding for more accurate baud rates
#define UART_B_VALUE (((F_CPU/BAUD_RATE)-20)/6)
#if UART_B_VALUE > 255
#error Baud rate too slow for soft UART
#endif
void uartDelay() {
__asm__ __volatile__ (
"ldi r25,%[count]\n"
"1:dec r25\n"
"brne 1b\n"
"ret\n"
::[count] "M" (UART_B_VALUE)
);
}
#endif
void getNch(uint8_t count) {
do getch(); while (--count);
verifySpace();
}
void verifySpace() {
if (getch() != CRC_EOP) {
watchdogConfig(WATCHDOG_16MS); // shorten WD timeout
while (1) // and busy-loop so that WD causes
; // a reset and app start.
}
putch(STK_INSYNC);
}
#if LED_START_FLASHES > 0
void flash_led(uint8_t count) {
do {
TCNT1 = -(F_CPU/(1024*16));
TIFR1 = _BV(TOV1);
while(!(TIFR1 & _BV(TOV1)));
#if defined(__AVR_ATmega8__) || defined(__AVR_ATmega8515__) || defined(__AVR_ATmega8535__) \
|| defined(__AVR_ATmega16__) || defined(__AVR_ATmega162__) || defined(__AVR_ATmega32__) \
|| defined(__AVR_ATmega64__) || defined(__AVR_ATmega128__)
LED_PORT ^= _BV(LED);
#else
LED_PIN |= _BV(LED);
#endif
watchdogReset();
#ifndef SOFT_UART
/*
* While in theory, the STK500 initial commands would be buffered
* by the UART hardware, avrdude sends several attempts in rather
* quick succession, some of which will be lost and cause us to
* get out of sync. So if we see any data; stop blinking.
*/
if (UART_SRA & _BV(RXC0))
break;
#else
// This doesn't seem to work?
// if ((UART_PIN & (1<<UART_RX_BIT)) == 0)
// break; // detect start bit on soft uart too.
#endif
} while (--count);
}
#endif
// Watchdog functions. These are only safe with interrupts turned off.
void watchdogReset() {
__asm__ __volatile__ (
"wdr\n"
);
}
void watchdogConfig(uint8_t x) {
WDTCSR = _BV(WDCE) | _BV(WDE);
WDTCSR = x;
}
/*
* void writebuffer(memtype, buffer, address, length)
*/
static inline void writebuffer(int8_t memtype, addr16_t mybuff,