Bent Genny Part #3 - Posted

[FrankG]

http://www.theworkshop.ca/energy/bengen/3/bengen3.htm

[sdscott]

Thanks for taking the time to post this execllent artical.  I have been planning to put Glenn's PicLog to work in my RE project (got all the parts).  It is interesting to see your stats!

Cheers!

[Jon Miller]

Hi Frank.  Read about the mistake, didn't mean to embarrass you!  Must say though, the project has come together nicely and shows the patients I sadly lack.

Whish you best luck with your next project, what ever that may be?

Regards

[Boondocker]

Great Post,

I'm embarking on a similar project using Parallax BasicStamp2 and StampPlot, first mircocontroller project.  

Wondering on the voltage ADC segment, is it scaled from 0 volts to max volts?  Or were you able to adjust the zero to be begin reading say at 10 vots for better resolution?

[FrankG]

SDScott & Jon,

Thanks for the kind words... The datalogger was a blast to make and even to use (for now...)

Boondocker,

The ADC input is reading @ 10bit resolution from 0V to 5V max (actually 6V but in this case it's limited by the VCC of 5V). Glenn @ thethebackshed.com designed the unit so he really is the final authority.

I do know that there is voltage divider on the V adc line with a note to change it from 22k to 39K ohm for 24V operation rather than 12V.

That may be the only drawback of building some elses circuit, the intimate knowledge that comes with designing it yourself... Though I have to say this was quite painless compared to some of the stuff I've hacked out on my own.

[sdscott]

Boondocker,  Glenn offers the source code for the PicAxe and the associated logging-software.  It is refreshing just how well written and simple his code is.  The voltage divider provides a safe(0-5volt) input to the PicAxe, which is then digitized to 10-bit-resolution.  The software does the math to convert this back to the real analog battery voltage of 0-12volts.  

This little chip is meant for elementary learning, but proves as a very useful and flexible tool.

Cheers!

[tecker]

I'll look into a linux port

[tecker]

I just had a look at the assembler" fun .I put the manuel in my files .Looks doable

http://www.otherpower.com/images/scimages/1431/picaxe_manual1.pdf

http://www.otherpower.com/images/scimages/1431/picaxe_manual2.pdf

http://www.otherpower.com/images/scimages/1431/picaxe_manual3.pdf

[Boondocker]

Frank SdScott

A difference between PicAxe and BasicStamp2, BS2 inputs have to be digital while PicAxe will take analog signal directly and converts it internally.   I will have to run the 0-5 dcv thru an ADC chip first then into the BS2.

This make using BS2 a little more complicated.  Now that I know more, my next project may use a PicAxe chip instead.