Hello. I'm working on the expandable Larson Scanner project, and I think I may have hit a wall in the programming part.
I've got two of the kits assembled each with a 6 pin jumper, and the USBTinyISP assembled with avrdude and the usb drivers installed as well, on a 32 bit Windows Vista system.
I've downloaded the Larson Scanner code and looked at the Makefile but I have to admit as a beginner I'm a bit confused. I can't tell if I am supposed to be re-setting the fuses or not, and as this is for a halloween costume on Friday I really don't want to brick the thing.
These are the links that I've looked at...
http://www.ladyada.net/learn/avr/avrdude.html
http://www.ladyada.net/learn/avr/fuses.html
http://www.vonnieda.org/software/avrfuses
as well as the makefile, as I've mentioned.
Can anyone who has done this before offer me any insight? I see the command that I'd use to change them, I'm just not sure if I should be and what the values would be to plug into the calculator if so, or if I can use the info at the end of the makefile?
Thanks for any info

If you're worried about bricking your chips, *do not* change the fuse values unless you have a specific reason to do so. Just use the makefile that came with the code-- without changing it --and you should be OK.

Excellent, thanks for the reassurance! While I'm on here, can I ask another question? I'm reading the AVR tutorial on ladyada and I feel clear on everything up to the actual command to type in the terminal wondow. The example is:
avrdude -c usbtiny -p attiny2313 -U flash:w:test_leds.hex

Which mostly matches with my scenario as I have the usbtiny and the attiny2313 chip. I understand that the w:test_leds.hex is to write the test led hex code they suggest, and I think I'm supposed to plug in what I actually want to program there (after the w: ), but that is what I'm not sure about . In the Larson_extend file folder there is nothing with a file type .hex. Am I supposed to copy/pasta the information in the makefile or use one of the other files? I feel like it's probably one of the other files, but I'm clearly fumbling around in the darkness here...

Oh and since the kits are wired together do you have to install the updated code on both attiny's? I've also got a 6 pin header on each board, just in case. I'm assuming yes, because how would it know which one to pay attention to, program-wise, if there was conflicting information on the chips?

Thanks again for any insight or tips. This stuff is pretty cool!

Normally, one uses the makefile to automate the installation process. Open a terminal window, move to the directory with the C file and makefile, and type the following two lines

make all <return>
make install <return>

The first compiles the code and makes the hex file. The second calls the avrdude command, with the right name for the hex file already selected. You may need to edit the top of the makefile to indicate which programmer you have, or other such details. Of course, if you prefer to use the avrdude command manually, you can do that too.

>Oh and since the kits are wired together do you have to install the updated code on both attiny's?

Yes, each chip is an independent computer, and requires independent programming.

The programming worked! It worked!
I see in the .c file where the steps you just gave me were listed, thanks for being redundant and typing it out again for me, that seemed a much easier way to do it.

I do have another question, I'm sorry they keep popping up (but I guess that's what the forum is for)!
The programming worked for both chips, they have been wired together as per the illustrations and photos in the article, but the only way I can get the sequence to work in both boards is to have the usbtiny plugged in to one of them then hit the control switch. It's ok if I switch the power on from the battery pack and remove the ubstiny connector, but if the power gets shut off from the battery pack after that, it only works on the one board. This is what I've tried, step by step:
USBtiny plugged in to either left or right board, hit control switch on either left or right board-works
While USBtiny is plugged in, turn battery pack to on, remove USBtiny, still works
After USBtiny unplugged, turn off power from battery switch (powers off)
Turn battery power switch back on (it's connected to what I'll call the left board) hit control button on the right board, nothing. Hit control button on the left board, lights up as per program, but only the left board.
Turn battery power off, hold down right control button while powering on, lights flash on only the right board
Repeat this step while holding down the control button on the left hand board, only the left hand lights flash.

What gives, am I missing something totally obvious?

Logically speaking it would seem to me that both chips are programmed correctly and that they are wired together correctly in the sense of sending the light sequence signal back and forth, since they both work with the USBtiny, and they are obviously both getting power but only one at a time when connected to the battery pack.

the only way I can get the sequence to work in both boards is to have the usbtiny plugged in to one of them then hit the control switch. It's ok if I switch the power on from the battery pack and remove the ubstiny connector, but if the power gets shut off from the battery pack after that, it only works on the one board. This is what I've tried, step by step:
USBtiny plugged in to either left or right board, hit control switch on either left or right board-works
While USBtiny is plugged in, turn battery pack to on, remove USBtiny, still works
After USBtiny unplugged, turn off power from battery switch (powers off)
Turn battery power switch back on (it's connected to what I'll call the left board) hit control button on the right board, nothing. Hit control button on the left board, lights up as per program, but only the left board.
Turn battery power off, hold down right control button while powering on, lights flash on only the right board
Repeat this step while holding down the control button on the left hand board, only the left hand lights flash.

What gives, am I missing something totally obvious?

Logically speaking it would seem to me that both chips are programmed correctly and that they are wired together correctly in the sense of sending the light sequence signal back and forth, since they both work with the USBtiny, and they are obviously both getting power but only one at a time when connected to the battery pack.

I'm not exactly sure what's going on here, but I'd suggest powering both boards from a *single* battery box. One pair of AA batteries provides *plently* of power for both boards, so add a pair of wires (+ to +, - to -) so that both boards can be powered together and turn on at the same time.

Quote by: Windell

I'm not exactly sure what's going on here, but I'd suggest powering both boards from a *single* battery box. One pair of AA batteries provides *plently* of power for both boards, so add a pair of wires (+ to +, - to -) so that both boards can be powered together and turn on at the same time.

Exactly what he said. The original expanded scanner, sitting here in my living room, is run off of a single battery box, and I think the directions I put together said something about running wires from one board to the other for power from the auxiliary power pads.

Actually, come to think of it, it *has* to be done this way, because then the chips share a common ground and can trigger each other correctly across the signal wires. If the power isn't connected between the boards (or, at a minimum, a shared ground), it can't trigger the inputs on the neighboring boards, and the light won't pass back and forth between them.