\dmc

It’s been a couple of years since I fiddled with this … but here are the parts that I believe I used:

http://www.mouser.com/Search/ProductDetail.aspx?R=140-50N5-270J-TB-RCvirtualkey21980000virtualkey140-50N5-270J-TB-RC

http://www.mouser.com/Search/ProductDetail.aspx?R=FOXSLF%2f080-20virtualkey55910000virtualkey559-FOXS080-20-LF

You’ll note that the crystal listed specifically calls for a 20pf capacitor rather than a 27pf … electronics experts have led me to believe that there isn’t much difference, electrically, from the 20pf to the 27pf, so I don’t think that is your problem.

HTH.

\dmc

Your problem is specific to your programmer and AVR Studio; I use AVRDude and the LadyAda USBtinyISP, so I can’t be much help here.

I’d suggest you find the forum for your programmer and ask for help there.

Best of luck.

\dmc

I’ve connected it all up, I get 2 green LED’s on the avr isp as hendrik, describes, after the following:

I open his text file in avr studio, power the transceiver. Then I compile and run the code. All is OK. Next I click connect button, choose avrispmk2 and usb and press connect. I get my 2 green leds on the avrisp, all is well.

Then when I try to read from the chip, I get “avr studio entering programming mode failed”

Why is this, I don’t understand, have I missed something critical?

Hope you can help,

Andy

Lots o’ questions:

So you are building based on Henne’s schematic at http://www.hoelscher-hi.de/hendrik/english/dimmer.htm ?

If so, using a 9v wall wart should be fine; if the wart is outputting DC, the rectifier in that circuit should just be redundant and shouldn’t be a problem. There should be no polarity issues either. My memory is that there is no “power” LED in the schematic, so when you are applying power before the chip is programmed, you shouldn’t see either LED light.

You are mixing up the meaning of “ground” and “earth” … the negative buss on the circuit does not go to “earth” (as in “grounded”) — it is just a common connection to the negative side of the circuit. It doesn’t need to go to “earth.”

You should be able to program the chip in-circuit, provided you give the circuit power. I believe the 10-pin AVR ISP header provides power, but the six-pin does not.

I am not familiar with the AVR ISP Mk2, so I Googled it. The picture looks like it has a ribbon cable coming out with a 2×3 connector on it. Henne’s schematic shows a straight row of six pins … you’ll need to change that to two rows of three pins. This is tough to do on a breadboard (you didn’t say whether you’re working on a bb or not). Short of buying something like this … http://zovirl.com/2007/10/21/avr-isp-header-for-breadboards/ … or this … http://www.sparkfun.com/commerce/product_info.php?products_id=8508 … you can make one up with a 2 x 3 header soldered to a piece of protoboard and then solder some wires to the pins. (Again, a quick Google found me this page, which has another alternative — bending the long pins on a 2 x 3 header: http://imakeprojects.com/Projects/avr-tutorial/ )

Once you apply power to the circuit and connect the ribbon cable to the header, you should be fine. You don’t need to jumper anything to put the chip into programming mode (that last URL is a good tutorial on programming an AVR chip).

Hope this helps.

\dmc

I am back on with the transceiver again, after some time! Any way I’ve built the board and have just bought an AVR ISP Mk2 to programme the chip. However…. I can’t seem to power up the board. Now my circuit understanding is very limited being quite new to all this, so excuse my dumb question…

I’ve built it and it looks like the one on hennes site. I have a Korg wall wart rate 9v 600ma which I believe meets the circuits requirements. But I’ve tried connecting it up and I get no lights on at all. I’ve attached the power to pins 1 and 2 next to the rectifier. I think this is right and it can take ac or dc, I am supplying DC.

So for the dumb question, does it matter which pin negative or positive go to and do I need to connect anything else to anything else. I have literally followed hennes instructions. So could you tell me what connections for both power and ground I need to make and where they go. Also what do you ground it to?

Do I need to programme the chip first or, as I am using and in circuit programmer do I need to power the circuit up?

What do I connect the isp’s 6 pins to in order to program the chip and does anything need to be jumpered to put the chip in to program mode?

Sorry for the newbie questions, but I hope you can help, this project has been dragging on for some time and it would be nice to get to the next stage of building some LED modules to control with it.

Thanks in advance,

Andy