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Nubie question: Programming ATMEL MEGA8

After looking over a lot of cool projects based on the ATMEL family of microcontroller, I just bought a bunch of ATMGAG8-16PI's. I bought these because I was under the impression these where very easy to play with:

  • On chip RC oscillator, no need for a crystal for simple stuff

  • Lots of I/O pins with decent source and sink capacity - can light up LED's directly

*A/D converter (might be fun to play with)

*No hardware programmer required - a few resistors hooked up to a PC's printer port.

*Lots of free tools - assemblers, compilers, libraries etc.

Ok, so I have a bunch of the chips and I have downloaded and built up the Linux AVR tools, the gcc cross compiler etc. I have also downloaded the AVR Studio from ATMEL.

Now, here is the thing, it seems that the Linux AVR tools will support the really simple "few resistor" type of programmer, whatever that is called. I am not sure if the AVR Studio or any windows 2000/XP software will support the same few resistor type programmer. I have been looking around and I have found:

  • A few of the few simple resistors and printer port based programmers. The gotcha is just about all of them use different pins on the printer port! They all use the same pins on the chip. Is there not a standard for this? How do you know what will work with what?

  • A few that look like the above but that terminate in a dedicated programming connection on the board with the micro. (JTAG?)

  • A few of them that hang off the printer port and use different amounts of old TTL logic between the printer port and the mico.

  • A few of the above that go into the dedicated connection on the board with the micro.

Are these guys cross compatible with the same programming software? Being a big fan of making my own life easy, why would you add more gunk between the two pieces?

  • Then there is the breed that hangs off the serial port on a PC.

  • Then there are the little dedicated "programmer" boards with the ZIF sockets and what seems to be a lot more silicon in the programmer itself.

So, can some kind soul tell me what the really cheep and easy "resistors and the printer port" type programmer is called and point me at some windows software that supports it (my linux box is a desktop in another room, and I would like to be able to program these from my notebook in the shop. The notebook runs XP and is unlikely to change)

Also, if you can elaborate on what makes the different types of these programmers "better" on "worse" then the other types. If I catch the bug I suspect I will upgrade if the other types do something neat or that can not be done with the Q&D ones.

Thanks in advance!

Matthew

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Reply to
beef
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IMHO your best bet would be to get the new AVRISP "MK II" programmer. It's USB-based, so obsolescence shouldn't be an issue for a couple of years at least. Relatively inexpensive.

There's support for it under Linux with AVRDUDE

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That page (and links from it) also describe some roll-yer-own programmers.

--
Rich Webb   Norfolk, VA
Reply to
Rich Webb

I will check out avrdude and see what he has. I am looking to do this as on the cheep as I can, so I am really looking for better into on the "few resistors hanging from the printer port" at least to get started. One of the really big things in favoe of these chips is that you do not need much to program them. Ideally this would be free out of junkbox parts.

Thanks again for the pointer to avrdude though, I will see what he has to offer.

--Matthew

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beef

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Reply to
Bryan Martin

Nothing wrong with that approach, of course, and it can be a fun project. The spec programmer, though, is only about $30 and takes away one variable when you're grinding your teeth wondering why the $%!&* thing won't program. ;-)

One hint for the ATmega-series: they come from the factory with the fuses set to run from the internal RC oscillator. On the one hand, this is a good thing since non-timer-critical applications can install and program the chip without having to have a clock source.

On the other hand, it's REALLY easy to forget this and wonder why a brand new chip refuses to program. The ISP freq needs to be

Reply to
Rich Webb

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