Step 5: Assembling the Board -€“ Part 1 -€“ Power

The first part to assembling the board will be the power section.

Take your LM7805 Voltage Regulator and place it somewhere at the top of your bread board similar to how it’s shown in the photo. When the regulator is facing you, the left pin is the input, the right pin is the output, and the center pin is the ground. Connect your 9 Volt battery connector to the input and ground. Then place a 10 uF capacitor between the input and ground and another between the output and ground.

Next place a 220 Ohm resistor plus the Red LED between the output and ground of the regulator. This is our power indication LED. Make sure the pin where the resistor and LED are connected is separate from any other pins we’ve used so far. The Resistor LED should be one path from the 5 volt output to ground and the short pin of the LED should be going to ground. Next you can connect the 5 volt output and ground to the rails on your breadboard. This will allow us to tap into the power and ground from the entire length of the breadboard.

That’s it for the 5 Volt power. For the 3.3 Volt power (if you chose to use it) simply follow the same guidelines as for the 5 volt power except for the following: It isn't shown on the schematics, but follows the same format, so you should be able to replicate it easily. THE PINS ARE DIFFERENT. Please review the datasheet for the pinout. The input to the 3.3 Volt Regulator will be the output of the 5 Volt regulator, you do not need an indication LED unless you would like one, and do not attach the output of the 3.3 volt regulator to the same rails the 5 volt regulator is attached to. I would just leave it in a small section on the other side of the breadboard for tapping into when needed.

<p>hi there just wondering , do all atmega chips come with arduino bootloader ?</p><p>or does it have to be specified at time of order</p>
Hi,<br><br>Atmel chips will not typically come with the arduino bootloader on them. Some websites will have them marked special like sparkfun or newark. <br><br>Take a look at this example:<br>https://www.sparkfun.com/products/10524<br><br>Another option is getting the atmega chip and using an isp (in circuit programmer) to program the chip or load the bootloader.
O.k. I got it now. Thank you very much! Thom
I don't understand where the 3.3v gets connected into the circuit. Can you be a little more explicit, please? Thank you, Thom Mulford
<p>Power is supplied by a 9 volt battery source. This is shown on the schematic as +9VOLT. This is then converted down to 5 volts using the voltage regulator chip (component LM7805 on the schematic). There are also a few capacitors and resistors involved in the power section. You can see all of these components at the top of the breadboard in Step 5: Assembling the Board - Part 1 - Power. From there, the stepped down voltage is fed into the power rails on the side of the breadboard. You can see these next to the red and blue lines running down either side (red for positive and blue for ground). The circuit can then tap into these rails anywhere along the breadboard for power. You should see the corresponding point in the schematic labeled &quot;+5V&quot; just above the green connection in the power section.</p>
<p>I had some problems getting a sketch to upload until I figured out <br> FTDI pin 4 goes to chip pin 2 and FTDI pin 5 goes to chip pin 3. This instructable has it reversed. Unfortunately I had just etched a PCB. :(</p>
<p>Wow, im really sorry about that mistake. I can't believe I haven't caught that yet. You are correct, RX should go to TX and TX to RX. I'll try to get an updated schematic loaded. Thanks for the catch!</p>
<p>Hey no worries, I found your instructable to great information and I appreciate the time you put into it!</p>
The 1uf electrolytic capacitor is not listed in step 1 or 2 or BOM or anything
<p>Sorry about that, it looks like i forgot to explain it. Your circuit may not actually require this component but I like to include it. It's going to help the FTDI chip get the reset pin held when it needs to reset the micro before programming. I believe most of the Arduino boards don't include this component.</p>
Great instructable!!! Maybe you could do one on how to build the FTDI breakout board, there's a schematic on sparkfun and it looks pretty easy
Hi. Thank you for the instructable. I followed the circuit but took out the power supply part (powering with the ftdi breakout) and also the reset button part as I don't think I need it in what I am trying to do. I bootloaded the atmega328p-pu and tried to run the Blink program. but. I am getting this error <br> <br> avrdude: stk500_getsync(): not in sync: resp=0x00. <br> <br>reading materials online for hours and I am not able to figure it out. I was wondering if you could point me in the direction so I could solve this issue. thank you.
<p>I apologize for such a late coming response.<br></p><p>If you havent found a solution yet....</p><p><br>You definitely need to have the reset circuit going. The programmer needs to reset the target immediately before programming it. I guess you could remove the button itself but make sure the pullups and programming connecting are still working properly.</p>
can i use this? http://www.ebay.com/itm/USB-To-RS232-TTL-PL2303HX-Auto-Converter-Module-Converter-Adapter-For-arduino-/180953299346?pt=LH_DefaultDomain_0&amp;hash=item2a21a83992
yea, this looks like it should work fine. Just be careful which power you use. You can only connect one to the circuit at a time. You should be able to you either 3.3 or 5 on the Atmega328 chip
It works but when you upload a program, you have press reset once the status says &quot;Uploading...&quot; <br>http://www.xappsoftware.com/wordpress/2012/04/16/how-to-upload-sketches-to-arduino-uno-chip-using-pl2303-usb-to-rs-232-converter/ <br> <br>I think the RX pin of the chip should be connected to the TX pin of the TTL converter and vice versa. <br> <br>Should the capacitor at pin 1 be reversed?
Just want to let you know that the reset capacitor is not really that critical. I have used a 100nF and even a 50nF capacitor and that worked well. Many FTDI boards may already have a capacitor in the reset line and if so, you do not need one on the breadboard.... as long as you remember this when you are using another FTDIadapter that may not have this capacitor :-)
Interesting. Just a 'word of warning' to people using a breadbord for this: I have build bare bone arduino's on breadboard and had many problems connecting to them (getting sync errors). Mostly this was because of the crystal -that has very thin pins- not connecting well in the breadboard. <br> <br>That is one of the reasons I always just build one on a PCB :-) cheaper as well. Nevertheless, great article, especially for the less electronically experienced amongst us
I can't guarantee from the picture, it looks like it should be fine as long as you wire it up correctly. Can you provide a link to the product somewhere so I can take a better look? <br> <br>Thanks
http://iteadstudio.com/store/index.php?main_page=product_info&amp;cPath=18&amp;products_id=94 <br> <br>http://www.simplelabs.co.in/content/ft232rl-tiny-breakout-foca-v21 <br> <br>both are same
Yea, this looks like a good deal. Basically looking that its F232RL and UART protocol, which it is.
Good work. Can you mention early that BOM means Bill of Materials? I was confused for awhile, because I'm not familiar with that term.
Thanks for the tip, i added a note about it in the second step.
Well documented.<br> I find AVR-labels to be very helpful with this. Here's some links:<br> <a href="https://www.instructables.com/id/Bare-Bones-Breadboard-Arduino-Labels/" rel="nofollow">Bare Bones Breadboard Arduino Labels</a><br> <a href="https://www.adafruit.com/blog/2011/11/09/adafruit-avr-sticker-for-breadboard-arduino-compatibles-10-pcs/" rel="nofollow">Adafruit AVR Sticker for Breadboard Arduino-compatibles &ndash; 10 pcs</a><br> <a href="http://todbot.com/blog/2009/05/23/arduino-chip-sticker-label/" rel="nofollow">Arduino chip sticker label</a> - I believe this is the original
AVR labels seem nice and convenient. Im used to looking back and forth at data sheets for pinout charts so i've never really used the labels myself.
very well documented, thanks for this!

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Bio: Electrical Engineer, control systems, automation, small electronics, home automation, microcontrollers etc.
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