AVR-Chat

Thanks, Dave!

I will do all of those. I also bought a better pre-fab 232 breakout board
today which will be delivered. I had soldered the leads from a usb-rs232
patch originally and it seems to be fine but I don't have a good way to
debug it. So, assuming whatever I buy should work, that should help to
narrow it down.



On Mon, Oct 24, 2011 at 12:15 AM, Dave McLaughlin <
dave_mclaughlin@nerdshack.com> wrote:

> **
>
>
> Hi Matt,
>
> My first thought looking at your image is that you have no capacitors
> fitted
> to the crystal circuit so you may have an unstable internal reference which
> may affect the baud rate.
>
> With the 16Mhz crystal I would suggest you put in a 22pF cap between each
> crystal pin and GND. This is shown in the datasheet for the device on page
> 30.
>
> I would also fit a reservoir capacitor on the output of the voltage
> regulator. Even though your load is very small, it is good practice to do
> this as those linear regulators are known to be noisy if not bypassed. Fit
> a
> 4.7uF Electrolytic (and a 0.1uF ceramic in parallel) between ground and the
> 5V output.
>
> You would be amazed at how often a microcontroller fails due to poor power
> supply decoupling. When I was first learning to do electronics and
> programming I used to just build without and wonder why it would crash
> every
> so often. After learning about good decoupling, my designs since then have
> been rock solid. :o)
>
> Hope you get it working.
>
> Dave.
>
> From: AVR-Chat@yahoogroups.com [mailto:AVR-Chat@yahoogroups.com] On Behalf
> Of Matthew Metzger
> Sent: 24 October 2011 01:08
> To: AVR-Chat@yahoogroups.com
> Subject: [AVR-Chat] Hello and Question
>
>
> Hello. I am new to the group and an am an amateur in the electronics field.
> I am looking forward to learning and participating.
>
> That having been said, I am trying to write code to an Atmega chip with the
> Arduino bootloader I've done this before with similar chips with different
> bootloaders without problem but I cannot seem to get it going on the
> arduino
> chip. Anyway, long story short, I used this video (
> http://www.youtube.com/user/Halo2maniaccc#p/u/9/VY0kiJNI5oE ) for
> direction.
> Here is my board ( http://centrasupport.com/electronics/Arduino.png ) I am
> using a different 16mhz crystal oscillator and, when I took this photo, was
> using a switch instead of a button for reset. I am now using a button. I
> get
> a blip in the blink pattern when I try to upload new code. But, at the end
> of all I always end up with the following:
>
> Binary sketch size: 1018 bytes (of a 32256 byte maximum)
> avrdude: stk500_getsync(): not in sync: resp=0x00
> avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51
>
> Any ideas on what I am doing wrong? I am also not opposed to building
> another board if someone has a better setup. The main requirement is that
> it's for the arduino bootloader.
>
> Thanks in advance for any advice you can give.
>
> - Matt
>
> [Non-text portions of this message have been removed]
>
>  
>


[Non-text portions of this message have been removed]