DIY LCD display temp/fan controller etc.

[Mark J]

Hi guys,

As some of you who were around in the early days of my marine keeping lark will know im a b*gger for having a go at DIY and saving a few quid etc.

Ive got a couple of PIC 18F2455 chips laying around along with a 2 line LCD and various electronic bits n bobs.

After looking about, I thought that when I get my new tank I want to make it look a BIT neater than having the old floating tube type thermomiter in the tank where you can guarantee it'll be floating all over the tank about 30 seconds after youve stuck it to the glass :rolleyes:

My plan is to have 2 temp probes, 1 for water temp and the other will be for reading the temp in the hood as I will be having a hood on this tank (not sure if its open backed or not, I forgot to ask Andy!)
But if its enclosed all around, even with just T5's in there, it could get a wee bit warm etc so I will have a couple of PC fans mounted (neatly lol) into the rear of the hood and also connected upto the PIC chip.

What will happen is, depending on if either of the temp probes hits the max level on temp, it will turn on the fans to either cool the water by blowing the fans over the surface or circulating the air in the hood to stop it geting too warm under the hood.

Will also be adding a few buttons to the project so that I can adjust the min/max values on both the hood and water temp start/stop values etc.

So at the mo, ive dusted off my PIC programmer and just wrote a little LED flasher code for the chip to 1. make sure the chip works still & 2. to make sure im not THAT rusty I just ended up blubbering at a blank screen lol!!

Will post pics as I go along and if anyone is into PIC programming etc and wants the code etc once its done, i'll gladly send it to you.

Mark.

PS. the PIC chip im using is a USB chip used to communicate with a pc etc, so maybe (a BIG maybe) in the future, I could see about actually hooking up the project to the PC and have data sent back and forth. (but dont count on it, as Im not overly bothered about that part lol)

[johnl69]

Sound like a good prodject, I have never tried programming PIC's to run an LCD is it easy to do?

[Electric Monk]

Sounds a top project.

When you get it working right don't forget to patent it and get it into production and charge us reefers 20 times more than it takes to make (we are used to that :eek::rolleyes::D)

[Mark J]

Sound like a good prodject, I have never tried programming PIC's to run an LCD is it easy to do?

Pic programming isnt too hard really, as rather than trying to use something like asm to write the code, I use picbasicpro which is great because it makes things a lot easier (and also dont have to write 2 pages of code to do a simple command etc!)

To run an LCD with the basic, it couldnt be simpler as the basic has its own LCDOUT command that does the main donkey work for you so you just tell it what you want on the screen and it displays it.

Just make sure the LCD is an hitachi made one (which most are anyway)

ElectricMonk:

You sure you only would want me to charge 20 times? could make it 30 or even 50 if you prefered LOL!!!!!! :D

[moorish]

sounds a good idea.derek

[Mark J]

Will be hooking up the LCD to the PIC chip and coding some stuff to get some text displayed on the screen later this eveing after ive stuffed my face lol!
If all goes to plan, i'll take a piccy of it breadboarded up and running with some text on the screen.

Once thats working, then will pop to Maplins and pick up a couple of the temp probes ready for the next step.

[stegoodall]

i was going to do a similar thing fo rmy computing a level project but went for something a lot easier in he end, basically a plug timer lol
i used a vellemann usb experiment board, i think this had analogue inputs so you could use one of these and use the inputs for temp. used the digital outputs to control relays for switching the mains

[Mark J]

Yeah I was in 2 minds, as reading some of the forums I use for PIC programming I had seen that the 18F2455 type chips were a bit of a git to setup etc, but with the new versions of the software and assemblers etc, it was a breeze! (was amazed my flashing LEd worked first time lol!)

Well, ive hooked up the LCD to the pic, and apart from 1 minor mistake on my part (ie, I had forgotten to actually supply the 5V to the LCD :rolleyes:) it worked first time! Amazing!
I honestly thought I would be farting about getting the LCD to work for a while but luck was on my side lol.

Went to Maplins and had to order a couple of temp sensors as per usual with our local shop they stock ****** all! So should be with me start of next week and then I can start tackling the temperature reading malarky ;)

Anyway, here's a pic of the breadboard with LCD running nicely (and to show its my LCD, read the text on it :D)

[Tangman]

Well done Mark when are they going to be in production m8 and how much will they be for forum members, maybe Macca could sell you some in the shop. HTH Twiggy:D

[Mark J]

hehehe erm ive not even looked at what the final cost will be as ive had the pic chips and the LCD laying around for a while , but I will do a total once its done (just hope I dont scare myself with it lol!)
To be honest, I think it would probably add up to more than just going out to buy a digital display temp sensor but then again, they dont have multiple sensors and the ones that can turn on and off fans are a fair bit more money than just the temp readers etc.

If all goes to plan, and I can find the info etc, I could always see about expanding the system to read other stuff too (ie ph etc) but will need to do some serious research for those things.