MAKE Magazine: Comments about Articles

Arduino? again.

alas, not at all.

Got it too

Took two attempts (new sheet of paper) and about a half hour. The order (color) of the houses falls out right away and the rest is just grunt work. Still, a good puzzle (any puzzle I can solve is a good one).

Arduino? again.

Now... what if... i purchased the ATtiny2313 microcontroller and used it with the arduino, and programmed it with the arduino ide... how well would that work?

Earthbox?

Anyone tried this with an Earthbox? It seems like it might be just as easy to keep the Earthbox full, as the feeder bucket. And then you can make do with only the photodiode and grow-light relay...

Arduino?

alas, i do grow weary of correcting myself. here are a couple of more trivial, but necessary changes. oc0a moves from portb on the tiny2313 to portd pin 6 on the mega168. oc1a on the mega168 is on portb pin1, which is used for an led on the brain machine.

Arduino?

sorry, the avrdude command line as given will give you a 1MHz clock. try this instead... avrdude -c usbtiny -p m168 -U lfuse:w:0x62:m

ever tried with an existing camera

I have an old view camera and was thinking this might work as a digital scanner for it.

Arduino?

just a little more information. to alter the arduino fuses to select the internal oscillator at 8MHz using a usbtinyisp from ladyada use the following from a command line - avrdude -c usbtiny -p m168 -U lfuse:w:0xf2:m then with the arduino still connected to the usbtinyisp start up the arduino environment and from the tools menu select boards, then lilypad arduino. then from the tools menu select burn bootloader then usbtinyisp.

Arduino?

couple of things to note. the big one is the clock rate. an arduino runs at twice the speed of a minipov3. pretty much everything in the brainmachine firmware is dependent on the clock. if you have an isp programmer, you can slow the arduino down and load the lilypad bootloader which is set up to run at the lower speed. second thing is that the registers used to put the processor to sleep at the end of the sequence are different. the code to put the arduino to sleep will be -


  SMCR &= ~((1 << SM2) | (1 << SM1) | (1 << SM0));
  SMCR |= (1 << SE);
  sleep_cpu ();

you won't be able to build the brain machine in the arduino environment, but you'll already have all the tools you need to build it from the command line. you'll have to modify a couple of lines in the Makefile that is used to build the brain machine firmware. the first three lines of Makefile should be -


MCU=atmega168
F_CPU=8000000
AVRDUDE_PROGRAMMER = stk500 -b 19200

once these changes are made you can just get to a command line and type make program-slm note that these suggestions are not tested, but are born of a good deal of experience playing with slm code for the arduino. best of luck.

Arduino?

Would the firmware with this project work if i wanted to use the arduino instead of the POV modification? If not, is there something minor i could tweak to make it work?

Nails

hi esqueleto, i placed the nails on opposite corners of a milk jug for my readings. if you're using different containers and/or different soil, you can set your own calibrations. for more advanced watering accuracy, borrow a water meter (here's one: http://www.growerssupply.com/farm/supplies/prod1;gs1_greenhouse_lighting-gs1_light_meters;pg105067.html )from a local gardening store and calibrate your sensor readings based on the water meter's readings at different levels of soil moisture. -luke

I think the wiring diagrams are wrong

hello morrildl, you're absolutely right: the illustaration on p. 95 shows the correct connection of ground to breadboard - and 5V to breadboard +, and the illustrations on 97 and 99 then show the incorrect connection. follow the text description and the picture on p. 95, and you'll get it right. thanks! -luke

Light problem

hi mtnbiker, this means you have the relay connected incorrectly. there should only be one connection per relay you need to change: looking at the relay with the pins down, the extension cord's output (the end to which you'll connect the lights) should be connected to the bottom right pin of the relay. if you turn the relay over, there will be a small number '4' written next to the correct pin. -luke

relay pins

the relay connection is one of the most difficult parts of the project. the diagram on page 99 is correct; here's a step-by-step guide to connecting them: http://garduino.dirtnail.com/makemag/stepbystep.html . also, here's step-by-step with video for the protoshield version: http://garduino.dirtnail.com/run1/ . -luke

Resitor location

Can anyone explain WHY this 'fix' works? It worked for me too, and I am surprised, since if there is an error in the original circuit diagram, I would have expected to find a reference to this somewhere. I mean, this circuit diagram is everywhere, and if there were a problem, you'd think there'd be mention of it. Any ideas? tnx, Vic