initial commit
This commit is contained in:
commit
914150f707
6
.gitignore
vendored
Normal file
6
.gitignore
vendored
Normal file
@ -0,0 +1,6 @@
|
||||
*.o
|
||||
*.elf
|
||||
*.bin
|
||||
*.hex
|
||||
*.lst
|
||||
*.map
|
||||
44
Makefile
Normal file
44
Makefile
Normal file
@ -0,0 +1,44 @@
|
||||
PRG = twiboot
|
||||
OBJ = main.o
|
||||
MCU_TARGET = atmega8
|
||||
OPTIMIZE = -Os
|
||||
|
||||
DEFS =
|
||||
LIBS =
|
||||
|
||||
# Override is only needed by avr-lib build system.
|
||||
override CFLAGS = -g -Wall $(OPTIMIZE) -mmcu=$(MCU_TARGET) $(DEFS)
|
||||
override LDFLAGS = -Wl,-Map,$(PRG).map,--section-start=.text=0x1C00
|
||||
|
||||
CC = avr-gcc
|
||||
OBJCOPY = avr-objcopy
|
||||
OBJDUMP = avr-objdump
|
||||
SIZE = avr-size
|
||||
|
||||
all: $(PRG).elf lst text
|
||||
$(SIZE) -x -A $(PRG).elf
|
||||
|
||||
$(PRG).elf: $(OBJ)
|
||||
$(CC) $(CFLAGS) $(LDFLAGS) -o $@ $^ $(LIBS)
|
||||
|
||||
clean:
|
||||
rm -rf *.o *.lst *.map $(PRG).elf *.hex *.bin
|
||||
|
||||
lst: $(PRG).lst
|
||||
|
||||
%.lst: %.elf
|
||||
$(OBJDUMP) -h -S $< > $@
|
||||
|
||||
text: hex bin
|
||||
|
||||
hex: $(PRG).hex
|
||||
bin: $(PRG).bin
|
||||
|
||||
%.hex: %.elf
|
||||
$(OBJCOPY) -j .text -j .data -O ihex $< $@
|
||||
|
||||
%.bin: %.elf
|
||||
$(OBJCOPY) -j .text -j .data -O binary $< $@
|
||||
|
||||
install: text
|
||||
uisp -dprog=avr910 -dserial=/dev/ttyS0 -dspeed=115200 -dpart=M8 --erase --upload if=$(PRG).hex
|
||||
294
main.c
Normal file
294
main.c
Normal file
@ -0,0 +1,294 @@
|
||||
/***************************************************************************
|
||||
* Copyright (C) 09/2007 by Olaf Rempel *
|
||||
* razzor@kopf-tisch.de *
|
||||
* *
|
||||
* 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; version 2 of the License, *
|
||||
* *
|
||||
* 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. *
|
||||
***************************************************************************/
|
||||
#include <avr/io.h>
|
||||
#include <avr/interrupt.h>
|
||||
#include <avr/boot.h>
|
||||
#include <avr/pgmspace.h>
|
||||
|
||||
#define F_CPU 8000000
|
||||
#include <util/delay.h>
|
||||
|
||||
#define LED_RT (1<<PORTB4)
|
||||
#define LED_GN (1<<PORTB5)
|
||||
|
||||
#define TWI_ADDRESS 0x21
|
||||
|
||||
#define APP_END 0x1C00
|
||||
|
||||
#define CMD_WAIT 0x00
|
||||
#define CMD_GET_INFO 0x10
|
||||
#define CMD_GET_SIGNATURE 0x11
|
||||
#define CMD_WRITE_FLASH 0x12
|
||||
#define CMD_READ_FLASH 0x13
|
||||
#define CMD_WRITE_EEPROM 0x14
|
||||
#define CMD_READ_EEPROM 0x15
|
||||
#define CMD_BOOT_APPLICATION 0x1F
|
||||
|
||||
/*
|
||||
* LED on PORTB4 blinks with 20Hz (while bootloader is running)
|
||||
* LED on PORTB5 blinks on TWI activity
|
||||
*
|
||||
* bootloader twi-protocol:
|
||||
* - get info about bootloader:
|
||||
* SLA+W, 0x10, SLA+R, {16 bytes}, STO
|
||||
*
|
||||
* - get signature bytes:
|
||||
* SLA+W, 0x11, SLA+R, {4 bytes}, STO
|
||||
*
|
||||
* - write one flash page (64bytes on mega8)
|
||||
* SLA+W, 0x12, addrh, addrl, {64 bytes}, STO
|
||||
*
|
||||
* - read one (or more) flash bytes
|
||||
* SLA+W, 0x13, addrh, addrl, SLA+R, {* bytes}, STO
|
||||
*
|
||||
* - write one (or more) eeprom bytes
|
||||
* SLA+W, 0x14, addrh, addrl, {* bytes}, STO
|
||||
*
|
||||
* - read one (or more) eeprom bytes
|
||||
* SLA+W, 0x15, addrh, addrl, SLA+R, {* bytes}, STO
|
||||
*
|
||||
* - boot application
|
||||
* SLA+W, 0x1F, STO
|
||||
*/
|
||||
|
||||
const static uint8_t info[16] = "TWIBOOT m8-v1.0";
|
||||
const static uint8_t signature[4] = { 0x1E, 0x93, 0x07, 0x00 };
|
||||
|
||||
/* wait 40 * 25ms = 1s */
|
||||
volatile static uint8_t boot_timeout = 40;
|
||||
volatile static uint8_t cmd = CMD_WAIT;
|
||||
|
||||
/* flash buffer */
|
||||
static uint8_t buf[SPM_PAGESIZE];
|
||||
static uint16_t addr;
|
||||
|
||||
void write_flash_page(void)
|
||||
{
|
||||
uint16_t pagestart = addr;
|
||||
uint8_t size = SPM_PAGESIZE;
|
||||
uint8_t *p = buf;
|
||||
|
||||
if (pagestart >= APP_END)
|
||||
return;
|
||||
|
||||
boot_page_erase(pagestart);
|
||||
boot_spm_busy_wait();
|
||||
|
||||
do {
|
||||
uint16_t data = *p++;
|
||||
data |= *p++ << 8;
|
||||
boot_page_fill(addr, data);
|
||||
|
||||
addr += 2;
|
||||
size -= 2;
|
||||
} while (size);
|
||||
|
||||
boot_page_write(pagestart);
|
||||
boot_spm_busy_wait();
|
||||
boot_rww_enable();
|
||||
}
|
||||
|
||||
void write_eeprom_byte(uint8_t val)
|
||||
{
|
||||
EEARL = addr;
|
||||
EEARH = (addr >> 8);
|
||||
EEDR = val;
|
||||
addr++;
|
||||
|
||||
EECR |= (1<<EEMWE);
|
||||
EECR |= (1<<EEWE);
|
||||
eeprom_busy_wait();
|
||||
}
|
||||
|
||||
ISR(TWI_vect)
|
||||
{
|
||||
static uint8_t bcnt = 0;
|
||||
|
||||
switch (TWSR & 0xF8) {
|
||||
/* SLA+W received, ACK returned -> receive data and ACK */
|
||||
case 0x60:
|
||||
bcnt = 0;
|
||||
PORTB |= LED_RT;
|
||||
TWCR |= (1<<TWINT) | (1<<TWEA);
|
||||
break;
|
||||
|
||||
/* prev. SLA+W, data received, ACK returned -> receive data and ACK */
|
||||
case 0x80:
|
||||
if (bcnt == 0) {
|
||||
cmd = TWDR;
|
||||
switch (cmd) {
|
||||
case CMD_GET_INFO:
|
||||
case CMD_GET_SIGNATURE:
|
||||
case CMD_WRITE_FLASH:
|
||||
case CMD_READ_FLASH:
|
||||
/* abort countdown */
|
||||
boot_timeout = 0;
|
||||
|
||||
case CMD_BOOT_APPLICATION:
|
||||
bcnt++;
|
||||
break;
|
||||
|
||||
default:
|
||||
cmd = CMD_WAIT;
|
||||
bcnt = 0;
|
||||
break;
|
||||
}
|
||||
|
||||
} else if (bcnt == 1) {
|
||||
addr = (TWDR << 8);
|
||||
bcnt++;
|
||||
|
||||
} else if (bcnt == 2) {
|
||||
addr |= TWDR;
|
||||
bcnt++;
|
||||
|
||||
} else if (bcnt >= 3 && cmd == CMD_WRITE_FLASH) {
|
||||
buf[bcnt -3] = TWDR;
|
||||
if (bcnt < sizeof(buf) +2) {
|
||||
bcnt++;
|
||||
|
||||
} else {
|
||||
write_flash_page();
|
||||
bcnt = 0;
|
||||
}
|
||||
|
||||
} else if (bcnt >= 3 && cmd == CMD_WRITE_EEPROM) {
|
||||
write_eeprom_byte(TWDR);
|
||||
bcnt++;
|
||||
}
|
||||
|
||||
TWCR |= (1<<TWINT) | (1<<TWEA);
|
||||
break;
|
||||
|
||||
/* SLA+R received, ACK returned -> send data */
|
||||
case 0xA8:
|
||||
bcnt = 0;
|
||||
PORTB |= LED_RT;
|
||||
|
||||
/* prev. SLA+R, data sent, ACK returned -> send data */
|
||||
case 0xB8:
|
||||
switch (cmd) {
|
||||
case CMD_GET_INFO:
|
||||
TWDR = info[bcnt++];
|
||||
bcnt %= sizeof(info);
|
||||
break;
|
||||
|
||||
case CMD_GET_SIGNATURE:
|
||||
TWDR = signature[bcnt++];
|
||||
bcnt %= sizeof(signature);
|
||||
break;
|
||||
|
||||
case CMD_READ_FLASH:
|
||||
TWDR = pgm_read_byte_near(addr++);
|
||||
break;
|
||||
|
||||
case CMD_READ_EEPROM:
|
||||
EEARL = addr;
|
||||
EEARH = (addr >> 8);
|
||||
EECR |= (1<<EERE);
|
||||
addr++;
|
||||
TWDR = EEDR;
|
||||
break;
|
||||
|
||||
default:
|
||||
TWDR = 0xFF;
|
||||
break;
|
||||
}
|
||||
|
||||
TWCR |= (1<<TWINT) | (1<<TWEA);
|
||||
break;
|
||||
|
||||
/* STOP or repeated START */
|
||||
case 0xA0:
|
||||
/* data sent, NACK returned */
|
||||
case 0xC0:
|
||||
PORTB &= ~LED_RT;
|
||||
TWCR |= (1<<TWINT) | (1<<TWEA);
|
||||
break;
|
||||
|
||||
/* illegal state -> reset hardware */
|
||||
case 0xF8:
|
||||
TWCR |= (1<<TWINT) | (1<<TWSTO) | (1<<TWEA);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
ISR(TIMER0_OVF_vect)
|
||||
{
|
||||
/* come back in 25ms (@8MHz) */
|
||||
TCNT0 = 0xFF - 195;
|
||||
|
||||
/* blink LED while running */
|
||||
PORTB ^= LED_GN;
|
||||
|
||||
/* count down for app-boot */
|
||||
if (boot_timeout > 1)
|
||||
boot_timeout--;
|
||||
|
||||
/* trigger app-boot */
|
||||
else if (boot_timeout == 1)
|
||||
cmd = CMD_BOOT_APPLICATION;
|
||||
}
|
||||
|
||||
static void (*jump_to_app)(void) = 0x0000;
|
||||
|
||||
int main(void)
|
||||
{
|
||||
DDRB = LED_GN | LED_RT;
|
||||
PORTB = LED_GN;
|
||||
|
||||
/* move tnterrupt-vectors to bootloader */
|
||||
GICR = (1<<IVCE);
|
||||
GICR = (1<<IVSEL);
|
||||
|
||||
/* timer0: running with F_CPU/1024 */
|
||||
TCCR0 = (1<<CS02) | (1<<CS00);
|
||||
|
||||
/* enable timer0 OVF interrupt */
|
||||
TIMSK |= (1<<TOIE0);
|
||||
|
||||
/* TWI init: set address, auto ACKs with interrupts */
|
||||
TWAR = (TWI_ADDRESS<<1);
|
||||
TWCR = (1<<TWEA) | (1<<TWEN) | (1<<TWIE);
|
||||
|
||||
sei();
|
||||
while (cmd != CMD_BOOT_APPLICATION);
|
||||
cli();
|
||||
|
||||
/* Disable TWI but keep address! */
|
||||
TWCR = 0x00;
|
||||
|
||||
/* disable timer0 */
|
||||
TIMSK = 0x00;
|
||||
TCCR0 = 0x00;
|
||||
|
||||
/* move interrupt vectors back to application */
|
||||
GICR = (1<<IVCE);
|
||||
GICR = 0x00;
|
||||
|
||||
PORTB = 0x00;
|
||||
|
||||
_delay_ms(25);
|
||||
_delay_ms(25);
|
||||
_delay_ms(25);
|
||||
_delay_ms(25);
|
||||
|
||||
jump_to_app();
|
||||
return 0;
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user