Hi,
I was wondering what is needed to make the atmega168 (or any of the DIP package chips) work. I mean the very least;
i.e. Using the internal 8MHz clock, programming it using a parallel port, any other tricks to remove componants.
Cheers
Hi,
I was wondering what is needed to make the atmega168 (or any of the DIP package chips) work. I mean the very least;
i.e. Using the internal 8MHz clock, programming it using a parallel port, any other tricks to remove componants.
Cheers
I don't know anything about the 8MHz clock, but other than that you'd need some way of powering it (I'd personally use a 9 volt connected to a 7805 Voltage Regulator - with capacitors as needed), and someone suggested a MAX232 chip along with a serial cable, or else a USB - RS232 Cable for programming.
I'm no expert, but that's all I think you'd need (unless of course I'm missing something obvious, which I have been prone to do ;)).
Thanks, I read somewhere on here (I think it was in a section on modifying the preference.txt files or simular) that the chip has an internal 8MHz clock (also in the datasheet - internal 8MHz clock and an internal 128 kHz low power clock).
I would use a parallel cable to program the chip so the rs232/usb would be obsolete.
So all I need is a power supply and a whole lotta research in how to get everything to work properly! :o
Sounds good to me :P. Just make sure the signals are compatible when programming so as to not fry your chip :P.
Just make sure the signals are compatible when programming so as to not fry your chip
Could you explain this a bit?
Thanks
At the very least, I think you can get by with no parts other than the power supply. This requires re-configuring the RESET pin and clock source via the fuses, and will require that you have a programmer than can still program the chip even when reset is disabled (I think this requires a "high" voltage on the Reset pin, so a simple parallel port programmer may not be sufficient.)
At this point, though, you're not very Arduino-compatible. You might as well hang out on AVR-freaks.net instead.
The minimum arduino-compatible system is probably a resistor from reset to Vcc, if you reprogram the fuses to run the internal clock and declare it as an 8-MHz lillypad...
personally your going to spend WAY more than the outrageous 95 cents that sparkfun sells a 16mhz ceramic oscillator dicking around with modding everything thats dependent on the clock
personally your going to spend WAY more than the outrageous 95 cents that sparkfun sells a 16mhz ceramic oscillator dicking around with modding everything thats dependent on the clock
Plus at the least $3.22 shipping ;).
This requires re-configuring the RESET pin and clock source via the fuses, and will require that you have a programmer than can still program the chip even when reset is disabled (I think this requires a "high" voltage on the Reset pin, so a simple parallel port programmer may not be sufficient.)
Reconfig the clock source is understandable, but why the reset? you do not need to do this if you programme with the ICSP on an Arduino so why now? All I was thinking was removing all parts not need to make an Arduino IDE compatable chip/board/circuit.
anything wrong with this :-/
Edit:
The minimum arduino-compatible system is probably a resistor from reset to Vcc, if you reprogram the fuses to run the internal clock and declare it as an 8-MHz lillypad...
Hmmm... maybe I should read posts 2 or 3 times before replying. :-[ Thanks
personally your going to spend WAY more than the outrageous 95 cents that sparkfun sells a 16mhz ceramic oscillator dicking around with modding everything thats dependent on the clock
How am I going to be spending more? All it is costing me is time, and I do it in my spare time when I am not working so essentually my time is free. So my time < $0.95. Although that is a bit depressing :-[!
well its not just the chip, its every piece of software that has perfect timing around 16mhz
so yea you might only spend a few moments resetting the fuses but how many days are you going to waste trying to figure out why (lets say) soft serial doesn't work
also in my world, where i also have a 80mhz 32 bit pic, i have hit the speed wall of the arduino a time or 2, and i havent even been around that long ... it boggles my mind why anyone would want to run it slower
Well there are certainly some applications that could work fine with a bare bones, minimum possible components, even with a slow internal R/C clock.
As long as you understand the purpose of all the various normal support function components then you are free to make the trade-off decisions based on good facts on if you want or should include them or not.
Lefty
Running at a slower speed uses less power, for example - why run at 16 MHz when all you are doing is sampling a temperature every 5 seconds, and updating a display or switching a relay. Less power, longer battery life.
Faster is not always better.
I realise some features are linked to the clock speed, but I probably wouldn't use any advanced features like serial comms on a basic setup like this. If I needed comms to a computer I would just use a Arduino board as it would have everything that I would need to easily communicate with a PC and less pissing around to do it.
It all comes down to fit for purpose, and not having a system that is hardware intensive but only uses the basic features.
The Arduino IDE seems a simple solution to program embeded chips that I dont want to buy a complete arduino for and do not require any further communication once programed.
so yea you might only spend a few moments resetting the fuses but how many days are you going to waste trying to figure out why (lets say) soft serial doesn't work
Probably not as long as you think, as I would know that I messed with the clock so one of the first things I would look at for troubleshotting is if anything I am doing is assuming the clock is still 16MHz
A point not mentioned here is that running off the internal clock gives you two more I/O pins, those formally used by the crystal. That means there is a straight byte output available. In some applications this might be desirable.
The whole of the art of electronics is that of a trade off between one thing and another.