AVR Development Board - Page 1
Forum section: electronics / beginners

author: Legion
author_rank: Frequent Contributor
timestamp: May 01, 2014, 12:23:20 pm
content: I'm trying to make the same type of dev board that Ben Heck did in this video:Unfortunately he doesn't provide a schematic, but he says he based it off a section of the Arduino Uno circuit. I tried to make my own schematic based off the Uno and what I saw in his video, but before I start soldering I was hoping you guys could take a look at the circuit and make sure I'm not missing anything. There are some elements I'm not sure about, some of the pins are prefixed with an "A", like "AREF" or "AVCC". Not sure if they're necessary for ICSP programming. I'm also not sure which capacitors are supposed to be paired with the crystal. It doesn't seem to specify in the schematic.Attached is my circuit in DipTrace and jpg.*Edit* Forgot to mention that I couldn't find the right parts for the pin headers so I just took anything that was square with the correct number of pins. So, that's not a card edge connector, it's actually a 10 pin female header. Also couldn't find the ATMega328P, so I used the ATMega48 which has the same pinout.

author: Rick Law
author_rank: Super Contributor
timestamp: May 01, 2014, 01:11:23 pm
content: This looks like the exact same circuit shown in the Arduino site on how to burn the bootloader onto the MCU on a breadboard using an Uno as programmer.The only difference I can see is they connect it to the digital-out pins rather than the ISP connector - both connector or pins ends up at the same spot on the ATMega anyhow. Also, they left all the other unnecessary connections out. Unnecessary in the sense that it is not needed for flashing the bootloader; whereas, this circuit (you attached) shows those unnecessary pins connected to a header for other (unrelated) use.If you are using the ATMega328, 16MHz crystal and 22pf would do nicely. I normally use 22pF/16MHz, but I've use 18pf with 4MHz crystal successfully. You can check the datasheet for acceptable ranges of values.AREF (external ADC reference) and AVCC (power for ADC - analog digital converter) are certainly not necessary for flashing. Take a look at the Arduino site on burning loader (target on breadboard with UNO as programmer), it will tell you exactly what is the minimum connection for flashing. The less complex, the higher the probability of getting it right with ease.All the pins are described in detail in the datasheet, and other info such as the recommended capacitor is detailed in the datasheet. I suggest at least look at it. If you are not sure what AREF/AVCC are for, it may benefit you to get a bit more familiar with the chip first.Rick

author: Legion
author_rank: Frequent Contributor
timestamp: May 01, 2014, 01:22:38 pm
content: Quote from: Rick Law on May 01, 2014, 01:11:23 pmDo you have a link to this schematic? I thought I found it on the arduino site, but clicking on the link gives me an error 404.

author: madires
author_rank: Super Contributor
timestamp: May 01, 2014, 02:09:53 pm
content: Quote from: Rick Law on May 01, 2014, 01:11:23 pmAVCC should be connected to VCC via a small inductor (10µH) and have a local bypass cap (100nF). If AVCC is not powered the ADC won't work. VCC should also have a local bypass cap (100nF). If AREF isn't used for an external voltage reference it should be buffered by a small cap (1nF). I'd make the cap optional to support both possibilities. Is that a switch between /RESET and ground? I'd replace it with a push button and add a 10k pull-up resistor. Without the pull-up resistor the ISP programming might not work properly. The ATmega has an internal pull-up resistor but attaching the ISP cable could trigger the reset easily.

author: Rick Law
author_rank: Super Contributor
timestamp: May 01, 2014, 02:10:49 pm
content: Quote from: Legion on May 01, 2014, 01:22:38 pmhttp://arduino.cc/en/Tutorial/ArduinoToBreadboardSomewhere in another article saying you should add a 10uF from reset to ground (on target MCU). I found that to help and remove occasional issues.

author: Bored@Work
author_rank: Super Contributor
timestamp: May 01, 2014, 04:05:43 pm
content: Get Atmel's application note AVR042AVR Hardware Design Considerationsand study it.

author: Simon
author_rank: Unknown
timestamp: May 01, 2014, 06:34:57 pm
content: yea the Ben Heck show, a total load of bolocks, usual corporate sponsored lack of information just to get their slimy name out there and some idiot that thinks he is cool signed up to be the face of that shit. I gave up within minutes. there is imparting information and there is talking rubbish and telling you how to suck eggs just to fill "show" time if you can call that abominal rubbish a show.

author: Unknown
author_rank: Unknown
timestamp: May 01, 2014, 07:01:06 pm
content: Quote from: Simon on May 01, 2014, 06:34:57 pmbolocks, slimy, idiot, shit, rubbish, suck, abominal .... I think you've succinctly expressed your dissatisfaction with Mr. Heck!I can't watch that show simply because his voice warbles so much. Give that man a spittoon!

author: SeanB
author_rank: Super Contributor
timestamp: May 01, 2014, 07:41:20 pm
content: Come on Simon, tell us how you really feel.

author: Simon
author_rank: Unknown
timestamp: May 01, 2014, 08:30:38 pm
content: Quote from: SeanB on May 01, 2014, 07:41:20 pmI hate bullshitespecially when I'm not paid to take it.

author: jancumps
author_rank: Unknown
timestamp: May 01, 2014, 08:35:11 pm
content: Quote from: Simon on May 01, 2014, 08:30:38 pmI don't agree with your view, but I like the way you word it

author: Simon
author_rank: Unknown
timestamp: May 01, 2014, 08:59:04 pm
content: The main problem I have is idiots like "Ben" trying to teach you to make a circuit board for an MCU system. You should not be messing with MCU's if you can't take a schematic and turn it into a real board. If you can't do that why the hell would you bother trying to make an MCU development board which if i got the jist was just a programming base so again hype over nothing.The net is full of assholes that think just because they can program in C they can take a development board and "do electronics" and that is what the Ben Hek show is aimed at. I doubt it's even his real name and hek who the hell would put their name to that crap. all he had to do was provide a schematic and maybe talk about layout. that peice of shit of a video has more special effects than content, sign of an asshole

author: zapta
author_rank: Super Contributor
timestamp: May 01, 2014, 11:56:19 pm
content: OP, if you are looking for a simple, 'from scratch' arduino schematic look at the schematic of this boardhttps://www.sparkfun.com/products/12640. It is supported natively by the Arduino IDE.The serial connection is intended to be used with something like this onehttps://www.sparkfun.com/products/9716(schematic available there).If you use blank MCU's, you will need to program the bootloader with the ICSP connectors (you will need a programmer).BTW, Chinese clones of the two boards are available on ebay for $4 and $8 respectively, taxed and shipped.

author: true
author_rank: Frequent Contributor
timestamp: May 02, 2014, 12:49:11 am
content: Quote from: Simon on May 01, 2014, 08:59:04 pmWho are you again? If you're someone important, maybe you should let the guys at arduino.cc know they released a product that people shouldn't mess with?Quote from: Simon on May 01, 2014, 08:59:04 pmHoly hell, the ignorance and fingers-in-ears-lalalala knows no bounds.Quote from: wilfredI will sometimes come across posts on EEVBlog and have to wonder "How can someone be so damn ignorant and/or hateful, especially when information is right here and/or there's nothing deserving of such hate," and most of the time the poster is this guy. I think he uses his protected status to rant and rave, push his points/agenda and generally be hateful more than anything else.edit: wrote "ears-in-finger" lol

author: Legion
author_rank: Frequent Contributor
timestamp: May 02, 2014, 01:29:09 am
content: Quote from: zapta on May 01, 2014, 11:56:19 pmThat's actually what got me interested in making a board like this. I recently acquired an Olimex clone of an AVR ISP MKII. I want to try working without the Arduino bootloader "training wheels".

author: retrolefty
author_rank: Super Contributor
timestamp: May 02, 2014, 03:13:36 am
content: Quote from: Legion on May 02, 2014, 01:29:09 amActually these days you can use the Arduino IDE to upload a sketch (program) using programmer option, thus not requiring a bootloader to be installed at all in the target device. The simplest/inexpensive programmer I have found that the Arduino IDE directly supports is the USBasp sold on E-bay for around $4 by a billion Chinese, work great.

author: Simon
author_rank: Unknown
timestamp: May 02, 2014, 05:43:29 pm
content: Quote from: true on May 02, 2014, 12:49:11 amReally ? I rant no more than the next user and anything like this from another user would have been allowed so where am i using my protected status ?, you clearly have your own problems, everything in that statement is untrue, you just want your own little corner to "rant" from yourself. Agenda ? what agenda have i ever pushed ? facts please!!! When i post i post as a user not as a moderator and if you had been around long enough or had been observant of how I and/or the forum works.

author: true
author_rank: Frequent Contributor
timestamp: May 03, 2014, 03:58:27 am
content: Allow me to go line by line, and then I will drop this, as this is wildly off-topic and will probably not accomplish anything. Feel free to split this off if you desire. If you have concerns, feel free to contact me directly and/or start (and notify me of) a thread relating to this.Quote from: Simon on May 02, 2014, 05:43:29 pmYes, another user saying this may have simply been accepted or ignored, but your post was with the weight of "Global Moderator" behind it. The post was a display of wilful ignorance (forming strong opinions after "giving up in minutes;" writing gems like, quoted verbatim, "doubt it's even his real name"), but this is the Internet, so I guess abusive and wilful ignorance is acceptable. However, it looks bad coming from a Global Mod of this community.Quote from: Simon on May 02, 2014, 05:43:29 pmHuh? Thanks for letting me know I have problems I guess? But why are you turning this into an attack?Quote from: Simon on May 02, 2014, 05:43:29 pmI wasn't the first to bring up the issue in this thread. I'm not alone to notice the poor judgement in behavior.This also isn't about me, and I don't want to rant about it. I won't write about further behavior like this if it bothers you.Quote from: Simon on May 02, 2014, 05:43:29 pmSure.https://www.eevblog.com/forum/microcontrollers/should-we-categorise-the-mcu-section/In this thread, you would repeat your point over and over, simply using new words to say the same thing in response to numerous valid counterpoints. The responses read like you ignored what was written and had to state your point again. I'm not saying that debate is invalid, but by passing off the responses you didn't like as unimportant, it certainly feels like the one in that thread is. Conversation in that thread reads like "Why are we even discussing this, I am right, let me repeat myself..."Not all agendas are major. This is just the latest one I have noticed. You are very opinionated (and many of us on this forum are) but you also aggressively push your opinions.Quote from: Simon on May 02, 2014, 05:43:29 pmI've been reading for a while now; my time spent here exceeds the age of my account. I've read a number of your posts. Generally, the above observations hold.Just so you know, every one of those posts looks similar and they look like this on the left side:This quite clearly reads "Global Moderator."

author: jancumps
author_rank: Unknown
timestamp: May 03, 2014, 06:30:54 am
content: Oh dear.

author: Simon
author_rank: Unknown
timestamp: May 03, 2014, 06:53:31 am
content: Quote from: wilfred on May 03, 2014, 12:44:33 amthen you have not been very observant, this is my only account and as with any forum a moderator is simply a user with the power to sort things out. I am not in anyway a representative of the forum. This is the same on any forum unless it is decided to have dual accounts. I have always been a user with the power to delete posts, modify them (in which case it shows publicly that 'i have) and ban people and i have always been very verbal about that fact that I am exercising as a moderator when I do so all arguments are baseless. I am as free as anyone to say what i like within the forum guidelines.

author: AlfBaz
author_rank: Super Contributor
timestamp: May 03, 2014, 07:03:08 am
content: Kudos Simon for expressing your views.I for one, thoroughly enjoyed your rant

author: Simon
author_rank: Unknown
timestamp: May 03, 2014, 07:04:27 am
content: Quote from: true on May 03, 2014, 03:58:27 amYour singling me out simply because I'm a moderator, you can say the same for anyone. Regarding the MCU section I thought it would help to categorize it. I first emailed Dave directly and suggested it. Dave said that he did not mind either way and that I should post the question on the forum. I did, yes i defended my point of view (and bearing in mind that not everyone reads every page of a topic before responding so I reiterated my thinking often) but it seems the opinion is to not categorize it and that has not been done. So what is your problem ?I was told when i took up being a moderator that it would be a thankless task, that person was right. This is an open forum run by volunteers, why do you moan like we are your national government ? My status will also apply to any post made since I joined but then it is been years now, funny that all of a sudden people have a problem. When we were a small forum (and i was equally opinionated) and we all saw more of each others posts and i posted much more often no one had a problem, now that we are bigger and posts are seen less and I post less members that have joined more recently suddenly have a problem. You seem to be misguided in how most forums work on the internet. I can give you the link to another forum I left due to agenda pushing if you like, if you want to see how bad it can get, where the whole forum will advise you to use assembler only because a nutcase moderator has his AGENDA about it and no one can contradict him, Where a moderator told me that I didn't need an RCD because it took amps of current to kill me not mA, you obviously don't understand what a great forum this is and what a bad forum is.....

author: zapta
author_rank: Super Contributor
timestamp: May 03, 2014, 12:54:17 pm
content: Quote from: Simon on May 03, 2014, 06:53:31 amYou do. With great power comes great responsibility.

author: Simon
author_rank: Unknown
timestamp: May 03, 2014, 01:48:25 pm
content: well thank you for re inventing the rules after 4 years. Things are what they are, have always been and that is that thank you very much !If your a Ben Heck fan i suggest you actually counter what i have to say instead of trying to attack my so called position.

author: zapta
author_rank: Super Contributor
timestamp: May 03, 2014, 02:03:32 pm
content: Quote from: Simon on May 03, 2014, 01:48:25 pmSimon, it's not about your positions, it's about the way you conduct yourself. People expect maturity from a global moderator.

author: ion
author_rank: Regular Contributor
timestamp: May 03, 2014, 03:18:30 pm
content: Quote from: Legion on May 02, 2014, 01:29:09 amIf you're uploading Arduino code to a blank MCU and you don't want to use a bootloader, don't forget to set the fuses. The first time I tried it I quickly learned the 328P isn't configured for a 16MHz external crystal from the factory.

author: Simon
author_rank: Unknown
timestamp: May 03, 2014, 03:19:23 pm
content: it comes as internal 1MHz but the fuses do more than that.

author: ion
author_rank: Regular Contributor
timestamp: May 03, 2014, 03:34:33 pm
content: Sure they do, but the speed was the most obvious clue that something wasn't right.

author: zapta
author_rank: Super Contributor
timestamp: May 03, 2014, 05:55:15 pm
content: Quote from: ion on May 03, 2014, 03:34:33 pmI had the same problem, clock was 1mhz, which means that you can program at most at 250khz and avrdude's default speed was higher so it didn't program. I had to use the -b option to show it down IIRC.

author: Simon
author_rank: Unknown
timestamp: May 03, 2014, 06:02:31 pm
content: use atmel studio, I've just done a tube-load, one of the main tabs has the speed.

author: zapta
author_rank: Super Contributor
timestamp: May 03, 2014, 11:55:40 pm
content: Quote from: Simon on May 03, 2014, 06:02:31 pmI tried it once but it's such a bloatware. We have a thread somewhere here about that topic. All I needed was the programming software. I then switched to avrdudes (the gui frontend) and am now using just a simple avrdude command line.

author: Simon
author_rank: Unknown
timestamp: May 04, 2014, 07:18:15 am
content: Yes it is a bit OTT but I find it easier to use than some obscure tool or command line. most MCU manufacturers seem to go the same way although Atmel seem to have gone the extra mile.

author: lapm
author_rank: Frequent Contributor
timestamp: May 04, 2014, 08:38:14 am
content: Quote from: Legion on May 01, 2014, 12:23:20 pmBen heck used ICSP, meaning simplified connection to target MCU and programmer... Theres excellent example in arduinos website how to use arduino as ICSP programming device.Basicly my only beef with Ben is that he docent really show things, he keeps quite shallow. The show is more like hey look what my employer wants me to mention this week..Basicly for ICSP you need just few pins connected on target MCU:Power: GND + VccReset lineData lines: MOSI, MISO and CLKyou can use avrdude or similar program with arduino ICSP...

author: Simon
author_rank: Unknown
timestamp: May 04, 2014, 09:12:18 am
content: that is what I was trying to point out but apparently as a moderator I'm not allowed an opinion. the board show is a target programmer NOT a development board, that is what the arduino is. The fact that that damn video is always tops in search results for AVR tells me that a lot of money has been ploughed into advertising. I think his video shows using a DIL socket when it would make more sense to use a zif socket which is what I did long ago. All you need is a bit of breadboard with a zif socket on it and the parts required to get the MCU up and running which would be power and crystal with caps if your going to use them in your final project. And no I didn't need to watch any video tutorial on how to do the obvious.

author: Legion
author_rank: Frequent Contributor
timestamp: May 04, 2014, 11:37:10 am
content: So I wired up a 328P to the Olimex AVR ISP MK2. Couple problems though. For some reason this Olimex programmer uses a 10 pin ICSP header instead of 6. I can get Atmel studio to see the programmer, but any attempts to read the device fail. Not sure if I trust "Olimex" brand and it's annoying that it uses a 10 pin header. Might just throw it out and get a proper AVR brand programmer.

author: Legion
author_rank: Frequent Contributor
timestamp: May 04, 2014, 11:43:39 am
content: Quote from: zapta on May 03, 2014, 11:55:40 pmVisual Studio is the dev environment I work in everyday. I was pleasantly surprised when I found out Atmel modified VS. Not having to learn a new environment lets me focus on the MCU.

author: zapta
author_rank: Super Contributor
timestamp: May 04, 2014, 02:12:37 pm
content: Quote from: lapm on May 04, 2014, 08:38:14 amIt's one of those shallow and cheerful diy shows that makes things looks much easier than they are. "Look how easy it's to build X when you have the money, machines, expertise and a supporting crew and you cherry pick what to show"It can be useful to inspire kids but in some way detached from the real world and can be frustrating when you try to apply it.

author: zapta
author_rank: Super Contributor
timestamp: May 04, 2014, 02:18:35 pm
content: Quote from: Legion on May 04, 2014, 11:37:10 amYou can get on eBay a cheap adapter from 10 to 6. Iirc, one row of the 10 is ground and then the other 5 connections.There are many cheap programmers that do work well. I am using atmel ISP mk2 which is not terribly expensive.

author: Legion
author_rank: Frequent Contributor
timestamp: May 04, 2014, 02:22:05 pm
content: Quote from: zapta on May 04, 2014, 02:18:35 pmOne row is 4 ground pins and 1 Vcc, the other row has all the data connections. I just manually adapted it for now, but it still didn't work. This programmer is an Olimex brand clone of the Atmel AVR ISP MK2.

author: Simon
author_rank: Unknown
timestamp: May 04, 2014, 02:40:48 pm
content: just buy the real thing, it's less than 40 quid

author: nowlan
author_rank: Frequent Contributor
timestamp: May 04, 2014, 02:46:37 pm
content: I was advised to get a legit AVR programmerisp mkIIfor $40 odd. I am sure the $5-15 on ebay work, but wanted to avoid any frustration with incompatibility.I ended up buying a dev board from deal extreme, except mine came with an LCD.JY-MCU Minimum AVR System Board (ATMEGA32). Ironically, I had issues with the programmer pin out being different. Also required a pull up resistor to stop the lcd pulling programming line down or something.I see some atmel nano boards on ebay for around $3. Sounds like a bargain. Look to be knock off of the teensy boards. I wasnt too interested in arduino and the shields.

author: Simon
author_rank: Unknown
timestamp: May 04, 2014, 02:49:46 pm
content: Quote from: zapta on May 04, 2014, 02:12:37 pmIt's just element14, farnell, newark or whatever the "Heck" they want to call themselves this day of the week have in mind as a way to break into the attention span of the newcomers to MCU's. so they just did a load of bloated crap and then paid google loads of money to make it show up in any search for AVR or similar. It is THE video of all that contains the least amount of information yet appears most often.

author: retrolefty
author_rank: Super Contributor
timestamp: May 04, 2014, 03:45:11 pm
content: QuoteI think you will find that those Asian E-bay $3 with 'nano' in their titles are really pro mini and lack the FTDI USB serial chip that a nano has. For example:http://www.ebay.com/itm/New-Pro-Mini-atmega328-5V-16M-Replace-ATmega128-Arduino-Compatible-Nano-d2-/151253230478?pt=LH_DefaultDomain_0&hash=item233765238eIs in fact a Pro-Mini clone. Where as a true Nano clone which does have the FTDI usb chip and usb connector start at around $6, still a great price.http://www.ebay.com/itm/New-Mini-USB-Nano-V3-0-ATmega328-5V-16M-Micro-controller-board-For-Arduino-/200964325858?pt=LH_DefaultDomain_0&hash=item2eca6841e2

author: Rick Law
author_rank: Super Contributor
timestamp: May 04, 2014, 04:42:33 pm
content: Quote from: lapm on May 04, 2014, 08:38:14 amThat is exactly why I point out the Arduino site's page on minimalist approach. It is so darn simple and it was made into something like rocket science.I think "minimalist way first" is the best way to approach learning. Like connecting a 7805 bare. Now as one encounter problems, one look at all those extras (like the decoupling caps) and one can then learn why they are there.

author: Simon
author_rank: Unknown
timestamp: May 04, 2014, 05:23:10 pm
content: this is what I made for burning arduino stuff or at least anything on an ATmega328 or similar with a 16MHz crystal, it will still work if I'm using internal clocks and I'm sure it will work on any program requiring a high frequency crystal as for just programming the frequency probably does not need to match the one attached. No 10+ minute video required......

author: madires
author_rank: Super Contributor
timestamp: May 05, 2014, 09:54:12 am
content: I can recommend the Diamex ALL-AVR which supports ISP, PDI and TPI (incl. 12V for a disabled reset pin). And it's not expensive, around 28 Euros. I'm using it for quite a while with avrdude and can't say anything bad about it.

author: Legion
author_rank: Frequent Contributor
timestamp: May 05, 2014, 01:42:29 pm
content: Quote from: Simon on May 04, 2014, 05:23:10 pmThe ZIF socket is a good idea. Added one to my order along with a proper Atmel AVR ISP MK2.