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I found was a resistance of ~5.5K ohms between the ground and +5v output of the voltage regulator (it's a LM7805C 5v voltage regulator) is this normal?
The value should be changing while you measure, as there should be capacitors from +5V to ground.
Hopefully you didn't measure with the controller in the circuit.
Another quick question, the tutorial said that the microcontroller was static sensetive can it also stop working through static while in the socket in the circut board?
It almost seems like your computer isn't recognizing the programmer more than something is wrong with your MCU. Did you try using the serial port your printer is connected to instead?
Quote from: agold on February 02, 2010, 12:16:32 AMAnother quick question, the tutorial said that the microcontroller was static sensetive can it also stop working through static while in the socket in the circut board?I don't think so. Yes the MCUs are static sensitive, but if it's just sitting in it's socket, it should be fine. I find it hard to believe you blew up your AtMega8. I've done some pretty bad things to mine and it still works wonderfully.
And the caps that Soeren is talking about are simply to give you a nice stable power supply. Adding caps between the battery terminals somewhat stabilizes the power from the battery, while adding caps between +5V and ground somewhat stabilize any power spikes that your circuit could draw. Are they always required for something to work? No. Should you have them anyway? Yes. If you followed the tutorial correctly when building the $50 dollar robot, your circuit should be fine, but for other applications/robots, you should probably include more power stabilization items (like caps between +5V and GND).
With the smoke test, if nothing smokes, you should be fine.
Caps are always required with a voltage regulator to avoid oscillations!Caps are always required with a controller, as high speed digital circuits draw current in sharp pulses, so they need the caps as local buffers for the supply, both to be able to draw the current and to do so without swamping the power bus with noise.
I'll have to disagree here.The "smoke test" is an old term from back when most components actually smoked when they died from over-current, but semiconductor (eg. a transistor or a controller) will die quite smokeless most of the time. These days, the term is just a leftover and "initial run" would be a more descriptive term to use.The smoke test is just the first run when you're absolutely (99.999%) sure there's no errors in neither the design nor the layout.You use the term on software (and even totally smoke-unrelated stuff) as well.
QuoteIt almost seems like your computer isn't recognizing the programmer more than something is wrong with your MCU. Did you try using the serial port your printer is connected to instead? Yes, first step is to get the OS to recognize the port.No program will gain access to ports that the system doesn't know of.
If you wanna tell other people what I'm on about, at least get it correct Caps are allways required with a voltage regulator to avoid oscillations!Caps are allways required with a controller, as high speed digital circuits draw current in sharp pulses, so they need the caps as local buffers for the supply, both to be able to draw the current and to do so without swamping the power bus with noise.
your operating system is only seeing 1 serial port and that's the one for your printer right?the printer plugged into an actual serial port or is is a USB one emulating a serial port?
what COM ports show up in device manager?if again it's only your printer, try checking you have your serial port hardware enabled in BIOS.
one thing you should try is make sure the serial port is enabled in BIOS.
can i just confirm something,you are trying to use a serial port on your PC right?on all home PCs less than 10 years old this will be a male 9 pin "D" shaped connector called a DB9.like this: http://images.google.ie/images?q=db9+connector
[...] any other ideas to find how to get to Bios?
You could try to find it on the web, by Googling "enter bios xxxx", where xxxx is the name and model of your PC or your motherboard - If you still have the mobo manual, that would be the place to find it.
I asked the IT expert at my school and he said that normally serial ports can't be disabled and that most likely something had blown - does that make sense?
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