Arduino uno custom board : code not getting uploaded.

Thanks for replying!first I used it with a laptop,it worked well.Now I am using it with my desktop,will there be any problem?  I am using it second time after a month....

YW. Are you using same Windows on both laptop and desktop? Are you using same USB cable? This message usually says bad communication between your PC and the arduino. Do you see arduino in device manager? In the IDE select port again...

Hi,

   it would be great if u could see the schematic and find out something.

No,it's not the same.And when I use update driver option,it is recognised as usb device not specifically as arduino r freeduino

As Lab assistant in robotics lab, I have encountered few problems when arduino USB to serial atmel chip got something wrong inside. Do not remember how they were acting. But I have found that sometimes this hapens with older firmware. So I got an Updated firmware (I think somewhere in arduino site) and uploaded using my mkII programmer. then it was ok. If USB to serial chip isn't atmel, but PL232 or something like this, then it may be chinies copy. and for thous new drivers give error "device can't start". then you need to use older drivers. I have pl232 vista (or PL2302). they work when you install them manually and from available drivers list select older one. And sometimes there is windows strange way of understanding serial device as a ball point mouse. It happens when arduino has a code inside wich seas for it to start sending something over serial as soon as arduino gets power. Maybe this is how windows detected Rs232 mouse in an old days. and some board types have more then one type of chip. be shure to select correct one.

I hope something got you on track.

Ramu

Lets start with the basics.

ENSURE you don't have anything plugged into Arduino Digital pins D0 or D1.

If you follow the troubleshooting guide here, you can then refer to where it stops.

Arduino - Troubleshooting

In particular you need to select the correct board as it sets up the communication spedd relative to the bootloader you installed into the 328 chip.

Windows does play funny with the UNO so check under the Device Manager when the board is plugged in.

Don't be afraid to delete the driver and start again.

Various antivirus software can interfere during the install process.

I'm curious about the answer to this question.

First, have you loaded the boot loader in the Arduino chip.

Your answer

Thanks Dave,

I have used atmega 16 u2 , and uploaded the firmware.

As far as I'm aware it is not possible to upload the bootloader using the serial connection on its own inot a raw chip.

So my question is ...

     Did you purchase a 328 chip with the bootloader already installed.?

     If so,  which version of bootloader is installed.?

re this

it is recognised as usb device not specifically as arduino r freeduino

The 16u2 will have a PID and UID programmed in which is licenced to arduino ... hence yours will be a standard USB connection.

For comparison the official UNO circuit is here.

http://arduino.cc/en/uploads/Main/arduino-uno-schematic.pdf

Mark

As I understand You use atmega16u2 for USB to Serial conversion. and uploaded firmware to it. So I hope it is the correct one but for your Atmega328 you need bootloader too. And that you can only do with programmer mkII or usbasp. In some cases you can use other arduino as a programmer.

Its all here: https://learn.sparkfun.com/tutorials/installing-an-arduino-bootloader/connecting-the-programmer

And like I sead. I do not know why, but sometimes atmega16u2 fails to program the main chip. I had this problem with 2 or 3 adruino boards (we have about 14 of them) over 23 or 3 years of using them. so this may be tour problem.

And like mcb1 seas, be shure not to connect anything to serial pins when programming it.

By the way. is your main chip showing any signs of life? can you use some programmer and read its signature and memory? Maybe it is dead?

The main chip is Atmega8a,it has a built in boot program.To burn it,which board has to be connected to the pc.I am just starting to learn programming with arduino.

Ok. in few projects we were using atmega8a with bootlouder ment for it. But it had problem if you were selecting board with atmega8. Sometimes it uploaded the code, sometimes it didn't. So one of the students were selecting arduino UNO (if I remember corectly). Then it was uploading. just this way before uplouding you have to see how much memory and ram the code is taking compiled. and see if it will fit. because atmega8a memory is smaller then atmega328p. Or you just can test with blink code. I was surprised that it worked, because there may be diference in addresing. but it worked. so if erything fales you can try it. But I advise you to rewrite firmware to atmega16u3 and atmega8 with programmer.

Ok,i will try rewriting with programmer and let u known the result.But even the blink program had the same error...