ATMega2560 standalone minimal - doesn't work

Other Hardware 3rd Party Boards
1

Hello,

I have make a circuit to use AtMega2560 stand alone (attach you can see the schematic: ATMEGA2560_V10.jpg).

I use MCU: ATMEGA2560-16AU
Programmer: USBASP V2.0

In Arduino IDE 1.0.5 I set

  • type arduino: "Arduino Mega 2560 or Mega ADK"
  • programmer: "USBAsp"

When i load bootloader i have this response:
avrdude: verification error, first mismatch at byte 0x1e000
0xff != 0x0d
avrdude: verification error; content mismatch

I have tried to load a sketch:

int led = 13;  //pin n.26 of AtMega2560

void setup() {                
  pinMode(led, OUTPUT);     
}

void loop() {
  digitalWrite(led, HIGH);   
  delay(1000);               
  digitalWrite(led, LOW);   
  delay(1000);               
}

I dont have any error while loaded, but the led doesnt blink it is still off.
What is wrong, can any suggest me or some solution.
Thank you.

(I have also make another board with AtMega328P and i can load bootloader and It works fine)

ATMEGA2560_V10.jpg
ATMEGA2560_V10.jpg600×614 47.5 KB

2

I would try removing the resistor and series led from SCK as the 200 ohm and LED would provide a pretty strong pulldown for the programmer to overcome.

(I'm not sure why you would want an LED on SCK)

3

Many Arduinos have the LED on SCK, one can only wonder why as it's not a great idea but it usually causes no issues. In this case with about 50 spare pins I'd use another pin for the LED. And yes 200R might be a little strong for the programmer.

paoloj, why do you have a 10-pin header for what I assume is the ICSP? Normally you have a 6-pin header, or is that compatible with the USBASP?

Rob

4

I'll try to remove the led.
I use 10pin header that is compatible with my USBASP V2.0 programmer.

5

I´m tring to do something like that, did you have any sucess?