Developing an Arduino Uno

[glenk]

Hi,
In my university me and another student have been tasked with adding an H-bridge into an Arduino UNO for use to help teach a class. We took the existing Arduino circuit and added an H-Bridge to it onto the PCB and had it manufactured. Once it came in it did not want to accept a program. It would always say stk500_getsync with a resp = number (neve 0x00 or 0xff). Could someone help me with that and clarify what our mistake was?

Thanks!

[markd833]

Without seeing the schematic for your new PCB we could only guess at the problem.

[PaulRB]

@glenk

clarify what our mistake was?

Two mistakes:

1. Imagining that even the best experts on this forum could possibly help you based on so little information
2. Having a board manufactured without building and testing a prototype first.

[groundFungus]

The very first thing that you should do is read the forum guidelines. There you will learn how to get the most from the forum. The forum guidelines.

[peposh]

It is hard to tell what happend without specific informations, schematic and pictures. It can be lots of things:
-software problems on your computer- arduino works without pcb?
-check usb cable
-chceck if arduino pins 0, 1(RX,TX) and reset(especially if your pcb is shield) isn't connected to something
-maybe your pcb draw too much current and power supply hasn't enough power
-if your project uses external power supply, you should always use this power supply while programming- in that case don't connect your device to usb only!
-there could be some shortage on pcb, which causes voltage dropout and arduino doesn't work
-there could be some shortage on pcb, which causes arduino burned out
-there could be some mistake in project, which causes both of the above

[TomGeorge]

Hi, @glenk
Welcome to the forum.

How to get the best out of this forum

See also FAQ - Arduino Forum for general rules on forum behaviour and etiquette. Hello, Welcome to the Arduino Forum. This guide explains how to get the best out of this forum. Please read and follow the instructions below. Being new here you might think this is having rules for the sake of rules, but that is not the case. If you don’t follow the guidelines all that happens is there is a long exchange of posts while we try to get you to tell us what we need in order to help you, which is fru…

Can you please post a copy of your circuit, in CAD or a picture of a hand drawn circuit in jpg, png?
Hand drawn and photographed is perfectly acceptable.
Please include ALL hardware, component names and pin labels.

Can you also post jpg images of your PCB design and image of your assembled board.

Did you prototype your project before going to PCB?

Thanks.. Tom....

[red_car]

@glenk

Could someone help me with that and clarify what our mistake was?

Yep... you made a mistake in the design of your PCB.

Someone will be able to tell you exactly what that mistake is... probably within an hour of you sharing your schematic and PCB layout.

[Grumpy_Mike]

Another guess for someone who didn't read the forum description before posting.

Have you put a boot loader in the 328 chip?

[srnet]

Or not programmed the ATMEGA16U.

Is there a prize for guessing correctly ?

[Grumpy_Mike]

@srnet

Is there a prize for guessing correctly

No but there are points.

And what do points mean...........

That joke will probably not be understood by anyone who has never lived in the UK.

@peposh we are just amusing ourselves while you get round to giving us some real information.

[srnet]

@Grumpy_Mike

That joke will probably not be understood by anyone who has never lived in the UK.

I doubt they will even have a clue.

[glenk]

Here is a screen shot of it

[glenk]

Based on the data sheet and comparing it to the actual Arduino UNO schematic, the only thing that is making a difference is the fact that Serial_RX and TX are flipped, but once I filled that (we are using the through hole variant of the Atmega328P, i just filpped using a jumper wire) it still did not want to work

[srnet]

What is the answer to the questions in post #8 and #9 ?

Both the ATMEGA328P and the ATMEGA16U need programs uploaded to them before the UNO will accept program uploads via the USB connector.

[glenk]

Do you have a link that shows me how to upload a program to the Atmega16U and Atmega328P? I tried using the Flip3.4.7 software that I saw and then burning the boatloader to the atemga328P, but it still did not work

[TomGeorge]

Hi, @glenk
You should be able to EXPORT a jpg image from the PCB CAD app.
A screen capture is not easy to read.

Thanks.. Tom...

[glenk]

The other student designed it before me. He sent the schematic to me as a PDF and he used JLCPCB EasyEDA as the program he used to design it and I can't get it to open in Fusion360. So that is the best I have right now. Sorry

[Grumpy_Mike]

@glenk

(we are using the through hole variant of the Atmega328P,

But your schematic says you are using an ATmega 8, not a ATmega 328.

Which one do you actually have on your board?

[glenk]

the 328P is the one we are using on the actual board

[TomGeorge]

Hi,

@glenk

The other student designed it before me. He sent the schematic to me as a PDF and he used JLCPCB EasyEDA as the program he used to design it and I can't get it to open in Fusion360. So that is the best I have right now. Sorry

Use JLCPCB EasyEDA to open the file.

Why didn't you make a PCB with the H-Bridge on it and using header sockets make it so you plug a UNO into it?
Make a H-Bridge shield.

NO hard work and if the students blow either up, then you only need to unplug and replace.

A UNO controller would probably be cheaper than all the assembly and parts you are now using?

It would make the UNO more versatile for other projects.

Tom..