So basically, I am trying to work with an AtTiny84, programming it from Arduino IDE 1.0.4 using ArduinoISP. I originally was using an AtTiny85, but realized that I needed more pins. I was able to successfully upload and run sketches on the AtTiny85, but I am having problems when I connect the AtTiny84 up to my Uno(r3) instead. When I attempt to upload a sketch, I get the following error:
avrdude: Yikes! Invalid device signature.
Double check connections and try again, or use -F to override
this check.
I've been following the instructions over at: http://hlt.media.mit.edu/?p=1695
As I said before, I had everything working fine with the AtTiny85 - it's just the 84 that is giving me problems. In my research on the problem, someone said that enabling verbose output in preferences might lend insight into this problem. Here is the output:
...
avrdude: Recv: . [10]
################################## | 100% 0.06s
avrdude: Device signature = 0x000000
avrdude: Yikes! Invalid device signature.
Double check connections and try again, or use -F to override
this check.
avrdude: Send: Q [51] [20]
avrdude: Recv: . [14]
avrdude: Recv: . [10]
avrdude done. Thank you.
If I have this correctly, the fact that the device signature is 0x000000 means that a connection could not be established with the tTiny, most likely because wires are mixed up. However, I've looked at it for a while, and I can't figure out how that could be. First off, I used the instructions in the link posted above to find out which pin numbers on the AtTiny hooked up to the Uno. Then, I used the AtTiny24/44/84 datasheet to find out which physical pins went with those pin numbers. I used pins PB0-PB3 on the left side of the chip, hooked up to the corresponding Uno pins. Then I realized that on the MIT site, they had a drawing with pins 0-3 being analog inputs, on the right side of the chip. I tried it both ways; neither worked. I had a 10uF capacitor on the Arduino to keep it from resetting, the chip connected to the Arduino's 5 volt supply, and the diagnostic LEDs hooked up throughout all of this. The heartbeat LED beats steadily, and the error LED blinks briefly after hitting the upload button. The "connection established" LED stays dark the whole time.
If it helps, I'm running Windows 7 Home Edition 64 bit, an Arduino Uno R3, and the part number of the AtTiny84 chip I am using is ATTINY84-20PU
I would really appreciate any ideas any of you might have; I haven't been able to find much information about the 84 on the internet, and can't think of any other things to try from my rather limited knowledge of microcontrollers.
Thanks,
thegadgetguy