Hi Guys
After installing Gerry Dupreys jSprinkler system in my small vegie patch and which has been running fine for quite a while now i decided to have a go at monitoring each vegie zones soil moisture. I initially had a play with using a sensor circuit connected to a DS10 device but thought that since my vegie patch is quite small a dedicated controller might be the best option....I scoured the net for a suitable solution without any luck..I did come across a project which i used the same method of sensing the soil moisture...
http://www.rgbled.org/sprinkler/index.html
http://www.bookcracker.com/projects/M278.html
For the controller i decided to use the same hardware that i use for my vegie sprinkler system which uses a pic16F877as the brains...This board sells for around $25 U.S. from futurelec...This device has lots of i/o and i was specially interested in the 8 analog inputs which im using as moisture inputs..
http://www.futurlec.com/PIC16F877_Controller.shtml
For the sensing probes i use some clipsal plastic conduit fittings , a 25mm coupling ,2 25mm end caps, 2 160mm long stainless steel 3mm threaded rod and a 3mm Bicoloured led and some 4 core security cable....The threaded rod is covered in clear heatshrink exposing the last 10 mm so that hopefully will give truer reading at root level...
I was looking around the net for some sample pic code asm or picbasic to get me started when i came across a link to an app which allows you to program pics or avr,s in PLC Ladder logic.. Afer some help from the author (jonathon) i got the board working reading a couple of probes that i had setup in pots for testing. The only issue i had was that i had to drop the baudrate on the serial connection as in recieve mode the board couldnt keep up when running at 9600/4800 baud so for reliable operation the baud was set at 2400....
http://cq.cx/ladder.pl
The board responds to queries from a host controller using a simple ascii protocol...To query zone 1 the host sends the following QAx.......which means it would like to Query Analog x ( 1 to 8) ...The Controller then replys val=xxxx were xxxx can be 0000 to 1023....
Since i use xPL and my Sprinkler system is controlled by xPL i thought it would be nice if i coulkd use xPL to control it...Not being a software programmer i made a request on the xPL Forum and luckily Mal Lansell ( xpl-rfxcom Guru) came to my rescue..So now using Mals app along with another xPL app xPL-Timer i am polling the probes once an hour
with 3 minutes intervals between each probe reading....I have a recurring event which trigger once every hour requesting zone 1 data..the controller reply triggers a 3 minute timer which will time out and request zone 2 data and this triggers zone 3 timer etc....
http://www.xplmonkey.com/
http://xplproject.org.uk/?page_id=2
Im not sure how successful this project is going to be , its early days..i,ll record the probes reading over the next few weeks and see if i can make sense of it ...If it does work out reasonably well i think i might have a go at making a pic interface to a DS10 device so i can use rf versions on my garden beds....
Some pics of my Moisture kit
http://s195.photobucket.com/albums/z38/fra...ture%20Monitor/
Frank
After installing Gerry Dupreys jSprinkler system in my small vegie patch and which has been running fine for quite a while now i decided to have a go at monitoring each vegie zones soil moisture. I initially had a play with using a sensor circuit connected to a DS10 device but thought that since my vegie patch is quite small a dedicated controller might be the best option....I scoured the net for a suitable solution without any luck..I did come across a project which i used the same method of sensing the soil moisture...
http://www.rgbled.org/sprinkler/index.html
http://www.bookcracker.com/projects/M278.html
For the controller i decided to use the same hardware that i use for my vegie sprinkler system which uses a pic16F877as the brains...This board sells for around $25 U.S. from futurelec...This device has lots of i/o and i was specially interested in the 8 analog inputs which im using as moisture inputs..
http://www.futurlec.com/PIC16F877_Controller.shtml
For the sensing probes i use some clipsal plastic conduit fittings , a 25mm coupling ,2 25mm end caps, 2 160mm long stainless steel 3mm threaded rod and a 3mm Bicoloured led and some 4 core security cable....The threaded rod is covered in clear heatshrink exposing the last 10 mm so that hopefully will give truer reading at root level...
I was looking around the net for some sample pic code asm or picbasic to get me started when i came across a link to an app which allows you to program pics or avr,s in PLC Ladder logic.. Afer some help from the author (jonathon) i got the board working reading a couple of probes that i had setup in pots for testing. The only issue i had was that i had to drop the baudrate on the serial connection as in recieve mode the board couldnt keep up when running at 9600/4800 baud so for reliable operation the baud was set at 2400....
http://cq.cx/ladder.pl
The board responds to queries from a host controller using a simple ascii protocol...To query zone 1 the host sends the following QAx.......which means it would like to Query Analog x ( 1 to 8) ...The Controller then replys val=xxxx were xxxx can be 0000 to 1023....
Since i use xPL and my Sprinkler system is controlled by xPL i thought it would be nice if i coulkd use xPL to control it...Not being a software programmer i made a request on the xPL Forum and luckily Mal Lansell ( xpl-rfxcom Guru) came to my rescue..So now using Mals app along with another xPL app xPL-Timer i am polling the probes once an hour
with 3 minutes intervals between each probe reading....I have a recurring event which trigger once every hour requesting zone 1 data..the controller reply triggers a 3 minute timer which will time out and request zone 2 data and this triggers zone 3 timer etc....
http://www.xplmonkey.com/
http://xplproject.org.uk/?page_id=2
Im not sure how successful this project is going to be , its early days..i,ll record the probes reading over the next few weeks and see if i can make sense of it ...If it does work out reasonably well i think i might have a go at making a pic interface to a DS10 device so i can use rf versions on my garden beds....
Some pics of my Moisture kit
http://s195.photobucket.com/albums/z38/fra...ture%20Monitor/
Frank