Need Help with Custom Arduino Design

Forum 2005-2010 (read only) Hardware Development
1

Hi guys,

I have recently come across a problem, in which i have no idea whats wrong. Basically i designed an Arduino board based of the reference design for arduino pro 5V / 16 Mhz.

I am able to upload the bootloader (Arduino Duemilanove w/ 328) on it. But when i try to upload a sketch, i am having problems. It gives me an STK500 failure.

I am trying to attach my schematic pdf, can someone tell me how to do it here?

2

Certain things you can't do on your first post on these forums; posting a link is one of them - SPAM filter, you see...

First off - welcome.

Secondly, post another post, put your link to your schematic or whatnot there...

:slight_smile:

3

It sounds like the automatic reset circuit is not wired up or working. This is a capacitor from the DTR line to the reset line, with the reset line pulled up to 5V with a 10K.

4

Thanks alot for the welcome Crosh.
And thanks for the reply Grumpy_Mike.

I am going to see if your suggestion is causing the problem. Any idea on how i can post a pdf?

5

I am going to see if your suggestion is causing the problem.

Also, try pushing the reset button as soon as you see the compiled code size. That should do it just like the DTR line.

Any idea on how i can post a pdf?

You can't directly (you can imagine the server space it would use if everyone posted theirs). Try uploading it to another site and posting a link to it.

6

Ive done one recently as well.
http://scratchpad.thisandthose.org/scratchpad/article.php?story=20100715160140327
Works well. Auto reset is working now.

I found that I had some solder bridges on the dil socket and the pins to plug into the breadboard.
This broke the auto reset for me.
Its worth checking over everything if youve put yours on a pcb already.

I have seen I think atleast 4 similar posts about the auto reset on the forum so keep an eye on those to see if theres anything appropriate for you.

Gordon

7

Thanks, It still has problems, i am using the SMD 328 chip. I will try to remove the capacitor on the dtr pin.

8

Did you use a smd resonator or crystal? Double check the connections to make sure you didn't get a short (or open) in there. I ran into this problem on my last design where I could use the ISP, but not the bootloader.

9

hey guys, i got it to upload. And I fixed it with adding a through-hole ceramic 0.1 uf capacitor on the DTR cap. I however have another problem, on the board i have provisions for both 12V power input and the usb power input, i separated the regulated 5V from the usb 5V using a 100 ohm resistor. If i power the device with the external power supply and try to upload, i can't. But if i don't power the device and just rely on usb power, it uploads. Any explanations brothers?

10

You really need some way to select between the power sources or you'll have big problems. Early Arduino designs used a jumper, and that's probably your best option if you want to keep it simple.

Jon
Practical Arduino: www.practicalarduino.com

11

Have you guys had any problems uploading when you share the ground from the arduino with one of your external hardware circuits which is powered from another power source? because constantly i have to remove the ground connection before uploading. Why is that?

12

is there any pros i can email my pdf design too check if there will be any problems? I have to build quite a bit of these boards, and really could use some professional advice.