Temperature stuck. Broken board?

I got Prusa with Sanguinololu 1.3a and spiritner firmware. I'm using proterface as host software.

Problem is that pronterface shows that temp is 59 even if i unplug temp connector. It also shows that bed has 130 temp and i dont have bed. It worked before today but after i tried my DIY hot ends it suddenly stoped working during heating.

My computer crashed once but i'm not sure did it work after that.

I have tried to upload sprinter again but it didnt help.

Now i have tried windows and linux pronterface both of them shows it same way.

If i try to heat hot end, it gets hot but trys to heat more and more, but temp stays in 60.

Edited 2 time(s). Last edit at 04/28/2012 01:18PM by eniq1on.

i had a similar problem last week.

i basically shorted something out which reset everything.
after restarting everything i let the hot end warm up to then find that temp was not moving anywere
then something blew in the hotend (im guessing resistor cracked)

anyway i found that the 5v voltage regulator and also then atmega chip were getting very hot

fix was to replace the atmega chip as it was reading wrong from the temp sensors

hope it helps

I asked about my problem in #reprap. And they sayd that ADC (analog digital converter) is maybe broken. So i ordered 2 new chips.

Now everything works fine with new chip. I have seen some posts with similar problems and thay have caused when thermistor leg touched heater leg. So thats maybe happened to mee also. My insulation in wires had broken.

eniq1on Wrote:
-------------------------------------------------------
> Now everything works fine with new chip. I have
> seen some posts with similar problems and thay
> have caused when thermistor leg touched heater
> leg. So thats maybe happened to mee also. My
> insulation in wires had broken.

Just to bee sure what exactly what chip did you replace on your board? because I have the exact same problem with mine Sanguinololu, and I would much rather replace one thing instead off buying a new board.

//PeterOK

Hello

I have the same problem. I need a bit more instruction to help myself. Would someone knowledgeable please write out a step-by-step guide for those experiencing this same problem?

Useful info:
Which chip
Where to buy (how much?)
Perhaps a diagram of location on board
Any useful tips about removing it and replacing it

Regards

Picture [reprap.org]

Probably you have to replace this black big one (atmega 644P). I dont know maybe you may have some different problem but in my case that was the reason. Remember to fix the problem that caused this temperature stuck problem.

You also have to burn bootloader to new chip when you get it and then upload firmware and so on... In reprap wiki there is instructions to all of these.

Hello Eniq1on

I'm glad that this is plug and play. It was not clear to me that the ADC was in the atmega chip. Thanks for the prompt and courteous reply.

Regards

Hello All

As an update to this thread for future generations:

When ordering a new atmega644p or 1284p, it will not come with a boot loader (unless specified). This mean you can not upload the firmware via the sanguino.
The boot loader needs to be burned using a separate piece of hardware, after which the firware can be uploaded.
google "sanguinololu bootloader" for details. USBtiny works for the 644p but not the 1284p so do your research before ordering.

Regards