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Topic: Tutorial for hacking a CP2102 USB from ebay and uploading a sketch to an Atmega (Read 19458 times) previous topic - next topic

msev

Thank you very much, you are really kind! it would take ages for me to draw all the connections...I do quite well for a beginner in the schematic editor, but in the board editor I get into trouble :)..

Well I'd like it to be single sided (I think I've already mentioned that :D) and with a dip package atmega and other parts also normal size (let say 3mm leds) not smd size ..

And I'd like the optional parts also (I'm not sure about that pwr led, it just indicates the arduino is being powered right?) and do I need the reset switch, if I have autoreset? I'd like the layout for the programming pins to be as similar as they can be with the modified programmer we are talking about http://www.ebay.com/itm/USB-2-0-UART-TTL-6PIN-Module-Serial-Converter-CP2102-/370532286388?pt=PCC_Drives_Storage_Internal&hash=item564571ffb4#ht_2817wt_1110 ...
I guess I want a female connector if cp2102 has male pins.
I don't need ICSP.

Thats about it I guess :)

Also maybe I'd like a led on D13 so I can diagnose if the arduino is properly working with blink sketch (or which pin is it, I know I have a led that blinks on my nano if I upload the sketch on it, its permanently on the board).

Oh another thing, I'd like it to be drawn in Eagle :).

I have another question about the bootloader,..I shouldn't buy atmega with optiboot (or uno bootloader) right, but instead with duemilanove bootloader right?

retrolefty

Also maybe I'd like a led on D13 so I can diagnose if the arduino is properly working with blink sketch (or which pin is it, I know I have a led that blinks on my nano if I upload the sketch on it, its permanently on the board).

Physical chip pin 19 is the arduino digital pin 13. Just wire a resistor and led in series from that pin to ground, with the led cathode lead wired to ground. A 1K resistor is used in the standard arduino board.

Lefty



msev


Sure - which parts do you want to keep, and how do want the connector?


So you won't be designing it  =( :)


CrossRoads

Already designed - just needs a little tweaking.
Unfortunately only so many hours in a day, and I don't always get back to a thread I might be interested in (right away).
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

CrossRoads

I assume you can handle naming of pins on the board if I post the files?
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

msev

Yep that won't be a problem...I see its double sided right?  :), I'll have to learn the correct technique to line all the lines right  :)..
The board in your previous post isn't the same like in your last post right?

CrossRoads

Yes, double sided.
I let eagle auto-route it. It does okay if you  have good parts placement to begin with.
The design is almost the same, added a couple of caps to the +5 line, diode in parallel with the reset pullup resistor, the 3mm LED and current limit resistor, and put all the pins in one row to be breadboard friendly (assuming one installs right angle male header there).
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

msev


RandallR

Is anyone planning on sending this to a board house to have it fabricated? 

I like the breadboard friendly nature.  I currently use Nanos but I might like to try one of these boards.

CrossRoads

Several folks have asked - here are the eagle files for the single-sided board I posted earlier.
Remember,  I had not updated all the pin numbers, that was "left as an excercise for the reader".

Others had asked about a single-sided version. I'll post one of those in the next message.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

CrossRoads

Single sided board. Haven't tried to make the pins all along 1 edge.
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

gerg

I bought four of these a couple of months back at $2.84 delivered. They are still available. All have registered on the USB bus and two have been tested on all pins via volt meter (and an uno driving inputs) and python serial. So as far as I know, they are good-n-cheap. It has all of the signals broken out on three of the edges. I'm very happy with these.

http://www.ebay.com/itm/350499583299?ru=http%3A%2F%2Fwww.ebay.com%2Fsch%2Fi.html%3F_sacat%3DSee-All-Categories%26_from%3DR40%26_nkw%3D350499583299%26_rdc%3D1

I soldered headers to one of them and will do the same with at least a second. I also straightened and shortened the 90-degree headers on the end which came with it. ts now ready to plug into a set of complimentary headers on the bottom of my my arduino project board.

http://maniacalbits.blogspot.com

xl97

Got my two as well..

$2.95 shipped...

took a few weeks of course..

but came, and look fine.

work fine too (after you install drivers of course)..

I mo'd mine as well....

I cut off the last header.. and and attached 'two',, one in the same place.. and one that hangs over the side a bit.. then I jumpered this to the DTR pin.

I probably didnt need to keep the RESET pin..  but whatever..



tested and programmed a custom Arduino board with it.. for $3.00 I cant complain!


RandallR

Here is my hack for the CP2102.
1) Cut the reset trace.  This is the input to reset the CP2102.
2) Soldier a .1uF  cap from the DTR output to the Reset Pin

This now works great.

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