Water Feature -- Microcontroler System

[Clyd3]

Hi guys, this is a question, especially directed in Nigels, and any other controller pro's direction. I am busy designing a big water feature involving electrically controlled valves and lights and one big pump to blast the water. These all need to continue doing fancy patterns in a nice sequence, all electronic. This is actually becomming a kind of business deal, and I cant use outputs from the PC, I have to use a controller board!
The main reason I am posting, is I need suggestions on what microcontrollers I will need. I am hoping for a PIC/s, as I am most familiar with PICs. The thing is, I dont actually know too much about PICs, and I am new to PIC assembly, but I have done a tiny bit of PC assembly. What I really want to know is what controller can handle this as I need to be able to turn on and off approx. 100 switches in a specific sequence. If you know of any similar projects, have experience with fountains, valves or microcontrollers, or know of where I can look on the net for any similar things, please post or email me <james@cbusnet.com>. Lastly, in Nigels PIC tutorial, there is a 16F628 (If my memory is working), that wont have enough capabilities for this will it?
That last question should give you an idea of my level of understanding

 

[bmcculla]

My advice is to just get the top of the line PIC. For all the money spent on the pumps, valves, etc. an extra couple bucks for a really nice controller, that you know will meet your requirements, is worth it.

Brent

 

[Clyd3]

In that case, do you know what controller, preferably PIC is capable of doing all of this?

 

[checkmate]

100 switches? All independent?
Anyway, the highest speced chip in the PIC16 series is the 16F877. If you need higher speeds or memory or, as in your case, simply need as many I/O pins as possible, go for the PIC18 chips.

 

[Nigel Goodwin]

Basically all you are wanting is a sequencer, the only problem is the large number of outputs you want - there are a number of ways you could do this.

You could use any PIC, and expand it's output pins using serial to parallel TTL converter chips - often called 'port expanders'.

Or, you could use multiple PIC's, and link them together.

Suggestions of 'top of the range' PIC's are pretty pointless, it's a VERY! low spec project - a 'clockwork PIC' could do it :lol:

Personally, I'd go for the multiple PIC option, using one PIC as master (generating the patterns), and other PIC's as slaves - with them all linked via serial connections, in on one pin, and out on another to the next PIC. You can simple stack as many together as you need, and add more at a later date if required.

If you used 16F628's, these have 16 I/O pins, so allocating two for serial I/O leaves 14 available for driving your outputs. If you use a 16F877, which has 33 I/O pins, this potentially leaves 31 for your ouputs.

Again, personally, I'd probably go for the 16F628, the chips are cheap and they don't need an external oscillator - so it makes each PIC board extremely simple.

 

[Clyd3]

String of 16F628 Sound Good!!!!!!

Thanks a lot, I like the idea of using multiple 16F628 as these are the most easily available PICs for me, I actually have quite a few comming in the post. I am currently working on a method of wiring the valves and lights so that I wont need so many outputs. If you have any ideas please help. Also, I have another question which has been bothering me for months; What is VCC and all the other weird nameson ICs and stuff? I really want to know, because I am always making projects according to other peoples instructions, but I never really understand how the chips connections work.

 

[evandude]

not sure how efficient you need this to be, or how much you are willing to spend, but you might be interested in the OOPIC, it's based on a 16F877, has about 30 I/O, and has built-in headers (and full, easy-to-use support) for I2C networking. the modules are like 40 or 50 bucks apiece, but programming them is INCREDIBLY easy, since they're object-oriented. I guess it depends on how in-depth you want to get with the project.

 

[Nigel Goodwin]

not sure how efficient you need this to be, or how much you are willing to spend, but you might be interested in the OOPIC, it's based on a 16F877, has about 30 I/O, and has built-in headers (and full, easy-to-use support) for I2C networking. the modules are like 40 or 50 bucks apiece, but programming them is INCREDIBLY easy, since they're object-oriented. I guess it depends on how in-depth you want to get with the project.

I suppose it depends if you like 'object-oriented' programming? (I don't), certainly it would be an expensive way to build the project, you would need four of them - it would be much cheaper to use four plain 16F877's.

Clyd3 - if you look at my tutorial hardware pages, you will notice I don't use Vcc etc. I label the power connections +5V and Gnd, which I think is much clearer.

 

[Clyd3]

I agree, it is easier to understand if you write the values. But still, where can I find info which explains to me what VCC etc. mean?
Thanks a lot for all your help guys. As soon as I get the financing, I will get started on this project, and many others.
Lastly, I quite enjoy programming, so where can I find info on learning the basics of the code used in these PICs? I know Nigel's tutorials dont cover too much code, but rather the application for the PICs, which is more important for a beginner, but where will I go after I finish his tutorials?