Some question about Loop-Back Test Instructions

Dear all,

My board suddenly cannot upload all of the programs with error message "avrdude: stk500v2_ReceiveMessage(): timeout". I found that the Tx keep sending data back to the computer and cannot stop even though I upload a program to the board. Then I searched a related article in google, Loop-Back Test Instructions.

http://arduino.cc/forum/index.php?topic=73748.0

But I fail at step 3, Force the processor to remain in reset by connecting a jumper from RESET to GND. It is because the board without any response for reset when I connected a jumper from RESET to GND or push reset button. The Arduino Mega board just keep sending the data back to the Serial Monitor and ignore the reset signal. The data is from the previous uploaded program.

I also do not fully understand step 6 and 7 in that article. Is it mean I should upload a terminal application to the board within connecting a jumper from RESET to GND??

The other question is should I burn bootloader to the Arduino??

Some additional information is shown below, I use Arduino Mega 2560 R3 Arduino IDE version 1.0.4, I try to re-install the drive a few times Window XP

Thank you very much.

littleming: But I fail at step 3, Force the processor to remain in reset by connecting a jumper from RESET to GND. It is because the board without any response for reset when I connected a jumper from RESET to GND or push reset button. The Arduino Mega board just keep sending the data back to the Serial Monitor and ignore the reset signal. The data is from the previous uploaded program.

When you connect a jumper from RESET to GND the board continues transmitting data to Serial Monitor?

Yes. It keeps transmitting data to Serial Monitor. I cannot stop it.

Make absolutely certain the jumper you are using is not defective. And, is making good electrical contact.

Make absolutely certain you are connecting the jumper between RESET and GND.

I am really sure that the jumper is well connect between reset and ground.

I am not sure is it a ATMEGA 2560 is broken.

Other than the jumper between RESET and GND, is anything connected to your Mega? Do you have any shields connected to your Mega?

[quote author=Coding Badly link=topic=153736.msg1153610#msg1153610 date=1363111379]

Other than the jumper between RESET and GND, is anything connected to your Mega? Do you have any shields connected to your Mega? [/quote]

NO, I only connect the jumper between RESET and GND and the jumper between Tx and Rx without any shields or components.

The only thing left is to try to reprogram the bootloader using a high-voltage programmer.

[quote author=Coding Badly link=topic=153736.msg1154248#msg1154248 date=1363147609]

The only thing left is to try to reprogram the bootloader using a high-voltage programmer.

[/quote]

What is high-voltage programmer? Is it different with simple ISP?

Given what you’ve described there are two possibilities: the processor is toast; RESET has been disabled. I mention high-voltage programming because it allows programming a processor after RESET has been disabled. If that is what has happened high-voltage programming will allow you to “resurrect” your processor. It’s similar to what you understand to be ISP # but requires a 12V pulse applied to the RESET pin and a few more pins for programming.

A few folks on this forum have used this… http://mightyohm.com/blog/2008/09/arduino-based-avr-high-voltage-programmer/ …to resurrect a processor after RESET was disabled.

You can purchase programmers capable of high-voltage programming.

And, now that I’m writing this, I realize high-voltage programming may not work unless you cut the RESET-EN trace. The auto-reset circuitry may interfere with the 12V pulse.

# Atmel actually calls it “serial programming”. ISP (in-system programming) can refer to either “serial programming” (which is very similar to SPI and is what is most often discussed on this forum) or “parallel programming” (which is also called “high-voltage programming”).