Arduino bootloader sequence

3
votes

I have put together a Bareduino which is an ATmega328 on a breadboard. I have a transceiver chip (MAX233) connected to it and to my serial port adapter on my laptop. I haven't been able to upload any sketches yet. What is the bootloader sequence? Does the Arduiono send out a character first or does the IDE? What is it looking for?

I have a manual reset button. The ATmega328 comes with a bootloader and a program already in it to blink an LED on D13 (chip pin 19). The LED is blinking on and off at one second intervals so it appears to be running. I have ordered an FTDI board, but I scrounged up a MAX233 and thought I would give it a try. Sorry, not a coding question, but I am interested in learning about the bootloader sequence.

1
arduino
IIRC, the IDE sends/sets DTR, this reboots the board. the bootloader waits for a few seconds for a sketch, else runs the current sketch. The logical code for it is pretty simple. Just read it :) – leppie

1 Answers

3
votes

On bootlup, the Arduino waits for a signal from the IDE, if it doesn't get one, it runs the local program. Are you getting timeouts? Are you selecting the right com port and board type? depending on the boot loader installed on your chip, try duemilanove or uno. do you have the capacitor for auto reset installed?

see http://www.instructables.com/id/The-Embedded-Arduino-building-an-Arduino-into-a-p/