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[on:]

I have my atmega328p on a breadboard with an 8Mhz chip and the arduino IDE set to Pro Mini 3.3v 8Mhz although I am powering it with 5v for uploading. Then I have the serial lines and the reset line connecting to the arduino board that has no chip seated. I also have D13 connected from the breadboard to the arduino because I found that helps. However it will work sometimes and sometimes it won't. Right now it wont. And it continues to not work even after restarting everything. I have the correct com port selected. I always get :

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

Whenever I do get it to work it's always randomly, I can't pinpoint what fixes it. Am I missing anything here? I've done this quite a few times and it's always so finicky.

[Reply #1 on:]

One thing I'm noticing is that while it doesn't work, I am completely unable to use the reset pin. The reset button doesn't working and it doesn't even reset when I short it to ground without any other connections. What would cause this? I think it is the problem.

Thanks.

[Reply #2 on:]

Its working on my duemilanove clone. recheck connections and try to add a jumper between Vcc and RESET. but @ 8MHz internal RC oscillator you won't be able to use it for any kind of Serial or I2C communication..  I m facing communication problem with same @ 16MHz.. if you have solutions then please let me know..!
Thanks.

[Reply #3 on:]

I'm using an external oscillator. The problem seems to be that the reset wont pull down, not that it wont stay up. During upload I have the reset pin connected to the reset pin on the arduino so it should act exactly as it does on the board as far as I'm aware. Does anyone know why the arduino would refuse to reset when pulled directly to ground? I mean I have it completely disconnect from anything else, then I put a jumper straight to ground and it still operates normally, it wont reset.

[Reply #4 on:]

Hi,
   Your reset button looks wrongly wired to me.

   I usually have a 10K pull up directly from reset to 5V, then also a connection from reset to a push button which closes to ground when pushed.

   Reset if pin 1, I cant see which way around the chip is from  your picture, but I dont see any that looks like it would work connected to pin 1.

   I use a manual reset and have not tried using the auto reset from another board.

Duane B

[Reply #5 on:]

Like I said, the reset pin is wired to the reset pin on the arduino so it should act just like it does on the arduino.

But that's irrelevant because I cannot even pull it down manually. There's no problem with it being pulled up, it's running the last uploaded sketch just fine. I just can't get it to reset so it won't upload a new one.

[Reply #6 on:]

The attached picture doesn't look like something that should work - assuming a manual reset which is a reasonable first step towards auto reset.

Can you attach a picture of your latest effort including how you are pulling reset low.

Duane B

[Reply #7 on:]

Pin 1 is reset. In your picture it looks like you have one side of your switch going to pin4, with a resistor between the pin and ground. The other side of the switch then goes to Vcc on the other side of the board.

Pin1 should have a 10k resistor to Vcc. Then, from the pin side of that resistor you should go through a switch to ground. Your rest fromt he other Arduino then connects to that same point, onto the pin between it and the pullup resistor.

What is that large electrolytic capacitor in the bottom of the picture?

[Reply #8 on:]

That button and resistor are going into Digital pin 2 (chip pin 4) for my project, that is not the reset stuff. Pin one is connected only to the reset pin on the arduino. It is as though the reset pin were still seated in the arduino socket so it should act exactly as it does while seated in the arduino. The only difference is I am using an external 8Mhz chip so it will not upload properly while seated in the arduino.

When I say I am manually resetting it, I mean I am taking a jumper that is connected to pin 1 and physically shorting it to the ground rail. When I do this, the chip continues to operate. I am clicking my button and it is reading out on Serial right where it left off.

The cap is just for decoupling because that rail is so far away from the arduino. Removing it doesn't change anything.

edit:
I switched to a new atmega328 and it works fine now. I must've messed up the boot-loader somehow.