REALLY wish we had some kind of document telling us what these errors mean! Stuck at the point of trying to program the tempsensor program. Can't troubleshoot because I don't know what this error means, or what I should look for.

We'd be happy to help... but we can't see your screen. You need to provide either a screenshot (prefferable) or the text of the error. Also, a photo of your setup often helps.

Rick.

ok - I will set it up again and try it again. Error is appearing as a result of my trying to "make" tempsensor. Will be back shortly with the error message.

Here ya go - text of what's going on: douglas-johnsons-macbook-3:~ douglasjohnson$ cd /users/douglasjohnson/Documents/Code/tempsensor douglas-johnsons-macbook-3:tempsensor douglasjohnson$ make avrdude -c avr109 -p m168 -b 115200 -P /dev/ttyUSB0 -U flash:w:tempsensor.hex:a avrdude: ser_open(): can't open device "/dev/ttyUSB0": No such file or directory make: *** [tempsensor-upload] Error 1 douglas-johnsons-macbook-3:tempsensor douglasjohnson$

Update: I solved this part of the problem myself - I had forgotten to do the "10b" step where I have to change the device location in the AVRDUDEFLAGS line. I hope as I go along here I get some kind of an explanation for why that step is necessary, and what we are changing.

Anyhoo - now that I got past that, I have the following error:

douglas-johnsons-macbook-3:tempsensor douglasjohnson$ make avrdude -c avr109 -p m168 -b 115200 -P /dev/cu.PL2303-00002006 -U flash:w:tempsensor.hex:a

Connecting to programmer: .avrdude: butterfly_recv(): programmer is not responding make: *** [tempsensor-upload] Error 1 douglas-johnsons-macbook-3:tempsensor douglasjohnson$

New development - I haven't changed anything that I'm aware of, but now the program hangs.

douglas-johnsons-macbook-3:~ douglasjohnson$ cd /users/douglasjohnson/Documents/Code/tempsensor douglas-johnsons-macbook-3:tempsensor douglasjohnson$ make avrdude -c avr109 -p m168 -b 115200 -P /dev/cu.PL2303-00002006 -U flash:w:tempsensor.hex:a

It never gets past the above.

Further update: unplugged usb cable, re-plugged, and this time the program worked. Wish I knew what was happening so I knew how to troubleshoot when these things hapen.

new development - program tempsensor is running, but the display is hardly readable because the background pixels are quite dark. It this a contrast issue that I can attempt to correct?

problem was overvoltage. When the red battery clip lead popped off the board, I inadvertently put it back on the hot rail, not the input of the voltage regulator.

As far as "Further update: unplugged usb cable, re-plugged, and this time the program worked. Wish I knew what was happening so I knew how to troubleshoot when these things hapen."

I am sorry to say this but "IT IS A MAC THING", I know you usually hear that about windows, but I often experience what you are seeing on my mac mini and the solution is, as you said, unplug the usb and plug back in. There is too much voltage on the yellow wire which puts my and your mac into a zombie state (apparently not everybody's). Sometimes I even have to do, God forbid a reboot.

I have a spst switch on the yellow wire so that I do not have to keep unplugging and plugging back in the usb cable, as suggested by Humberto.

Ralph