Bootloader Atmega328 - AU

Hello All,
I am at the end of my choices to troubleshoot this bootloader problem.

I bought a SMD ATMEGA328-AU-ND create my own circuit board and have double checked all my
connections for power and ground and everything is correct.

I have double checked my connections to burn a bootloader to the chip is correct as well.
slave reset: 29 SMD ATMEGA328-AU-ND

Can anypone help me with this bootloader error.

This report would have more information with
"Show verbose output during compilation"
enabled in File > Preferences.
Arduino: 1.0.6 (Windows NT (unknown)), Board: "Arduino Uno"
avrdude: stk500_program_enable(): protocol error, expect=0x14, resp=0x50
avrdude: initialization failed, rc=-1
Double check connections and try again, or use -F to override
this check.

avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51

Is it true this chip can use the UNO or the Duemilanove 328 bootloader.

Help 8)

Hey i forgot to add I have been trying to use the UNO board as a ISP to load the bootloader.

I also own the TinyAVR and the Atmel mkii AVRisp programmer.

The chip can use the regular or optiboot bootloader. You may have more luck if you program it as a Nano rather than an Uno though.

I also noticed you have the regular 328-AU, not the pico 328P-AU. I don't think that Arduino IDE supports the non pico version without making changes to the avrdude.conf file. It's all to do with the pico chip having a differen device signature (1e 95 0f) where the non pico has 1e 95 14.


Thank for you for your response.

I changed to in avrdude.conf 1e 95 14. Now my error is:

avrdude: stk500_getsync(): not in sync: resp=0x00

Any idea's?

What happens when you use the MKii programmer? You have to supply power to the chip when you use it, the MKii only monitors the supply level, it does not supply it. The MKii must connect to power & gnd as well. Your board has all the VCC & AVCC pins powered up, and all the grounds connected?

Hello CrossRoads,
Thank you for the response. :grinning:
Yes I checked with a DMM GND and VCC & AVCC for power and yes it all connected. Let me look up the pin-out on the MKii and try it and get back to you.

You mean also I need to connect power and ground to the 6 pin header on the MKii programmer.

Yes, connect power & gnd to MKii. All 6 pins must be connected.
Red marked wire on MKii indicates pins 1/2 as seen "looking down"

1 MISO 2 +5
5 Reset 6 GND

and if you flip the connector over and look into the holes, it's:

2 +5 1 MISO
6 GND 5 Reset

Hello CrossRoads,
I wanted to tell you the AVRISP MKii worked. But after it programed it still would not do the blinking default program.

So I was like what am I doing wrong it programed but no blinking light. So I got out the DMM and test pin 29 if it was at GND all the time. I made a mistake on the PCB board.

I have included the picture of the board and had to break the trace and boom. Blinking led.YA YA YA
Made a board after 12 years and made some mistakes in the design. It’s a proto type but it’s working.
Version two will be fixed. Thank you for pushing me to get this fixed. Your help really made me push for an answer.

My kit is going to be a Arduino compatible stand alone kit. Most people build a project with Arduino and want to leave the board with project. Well here it is the assembly kit for stand alone projects.

Bootloader does not do blinking - you have to download the blink sketch for that.
When I make a new board, I do two things - burn a bootloader, and then download the blink sketch. That makes sure the two big interfaces are working.

What program did you make the board with? I use Eagle from
The freeware version will let you create 2-sided 80x100mm cards. You can get quite a lot in 80x100mm.
It has error checking on your schematic so you can find things that are not connected that might appear to be.
It has error checking on your board that can alert you to overlaps like that and other errors such as traces/pads/holes too close to each other, holes on top of holes, things too close to the edge of the board and to let you know if there are traces that are not routed yet.

Sparkfun has tutorials on it, as well as a list of things that will result in good boards.

How did you make the board? I have in China make mine - 2 sided, solder mask, labeled. Very pro looking when done. Examples here:

Hello CrossRoads,
Thanks for the quick reply. I was using expressPCB. Need to find a cheaper PCB company.
80mm x 100mm is 3 inch by 4 inch. How do you set the demotions in Eagle to only make a board that size.

A lot of manual settings. To costly as well. I did create the new version in Eagle and love it.

Currently I am trying to find all smd 805 size parts any tips.
On the bootloader blinking all the bootloader I have burned default blinking on out on pin 13.
With out uploaded a sketch. I did not have time last night to install the FTDI and try and upload a new sketch. However will do it tonight after work.

Eagle, layer 20 is the dimension layer. Draw a square, right click on the lines and set the dimensions to what you want.
With the free version, I think the board view will open to that size, and you make it smaller if you need to. 80x100 is nice because it's also the size of Velleman ECS 1/2 protoboard, and I build up prototypes on that size card. Figured if it fits there, it will fit on a PCB and can likely be routed.

I used ExpressPCB for one PCB, a simple block of LEDs, three transistors, a fourth transistor acting a signal inverter, and a voltage regulator. (I'd had this drawerful of transistors since college, seemed like a good time to use them - I'd use a ULN2003/2803 now tho). You can see the cards on the right & left of this box. Both were made from one card, which I hacksawed down the middle to make two. All lettering was done in copper on the top layer.
I still use it for quick designs for discussion here.
For PCBs tho, I use Eagle.