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Author Topic: peculiar speed up in the demi clock?  (Read 364 times)
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I run 2 demilenove's . Last night, on  both  units, the onboard leds suddenly went a lot faster--With a baud rate in the program of 9600, I now have to run the monitor at 19200 baud to get any sense. ( even tho' the program still is at 9600) The program collects data from 2 interrupts, massages the info and normally send to Pachube, via a processing program.  Any ideas what is going on?
Thought somebody with more sense than me could have an idea!
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Hmm, odd indeed.
Did you try a reset to see if things went back to normal?
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Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
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Thanks for the fast response, Crossroads. Yup, tried resetting. Also reloaded the programs, and even rebooted the PC before the download.Also tried loading different sketches, but same speed on the Arduino's. Funny thing is that both of the arduino's did it at the same time, so I guess this is not an intrinsic arduino fault. Could try another PC to reload the program!
Tnx S
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Do you have another ATMega chip to put in? Sounds like the timer for the UART is running at 2X.
Odd that both do it - any funny power glitches or anything occur, lightning nearby or anything?

The other thing you can try is looking at the fuse settings;
http://www.geocities.jp/arduino_diecimila/bootloader/index_en.html
I have a duemilanove set up like this, with some pins installed at the X3 location so I put jumpers from there to the ICSP header and read the fuses like as described.  Maybe knowing what they are set at will help. Or not.
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Wow-that is going to take me a bit of midnight reading to absorb this stuff! I do have a bit more data----on a different PC the reloading puts it back to the original speed. So I guess the problem lies with the down loading program or the PC itself. The PC works OK otherwise, in fact I am getting this message to you on it.
Might try downloading the program from PC no 2 and then feeding output to PC no 1, to see if the baud rate behaves itself.
This is the way Saturday afternoons disappear, my thanks for your help, S
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