Simple 'Door Alarm Circiut' Project

[OsMaN_93]

Hi,

I'm doing this project for school, where I chose to build a magnetic door alarm.
I'm struggling with building the circiut, i just find it really complex, to know what and where to put the different components. And before anyone accuses me of cheating, this isn't because the teacher actaully supports us to do independant research.

Here is a rough idea of what I want to make.

the system diagram:
**broken link removed**

So this is what I want it to do.I can provide more detail if you wish me to so so. Can someone here help me, please?

P.S. I'm 16, so i'm not a pro like you guys here

P.P.S I'm using a pic chip, building it through chip factory, where i will have a green light when the alarm is on, and a flashing red light and a buzzer for when the circiut is complete (door opened).

 

[vne147]

All of the features you mentioned can be accomplished with a PIC using a minimum number of external components. You'll have to use a little imagination for the "time entry delay" part of the alarm as there are multiple ways you could do this (i.e. keypad, light senser, micrphone, etc). Most of the challenge will come from writing the software that will go on the PIC. How much experience do you have with PICs and programming in general?

 

[OsMaN_93]

Hi, thanks for your reply.

I haven't made a pic chip before, but I had a go at making some functions today, using the high, out, low, wait etc. it looks easy, but it isn't... So I struggled and my 2 hr practicing time, turned out in vain, as I failed to build what I wanted :/

 

[vne147]

Hi, thanks for your reply.

I haven't made a pic chip before, but I had a go at making some functions today, using the high, out, low, wait etc. it looks easy, but it isn't... So I struggled and my 2 hr practicing time, turned out in vain, as I failed to build what I wanted :/

If you've never played with PICs before, it is going to take you a little longer than 2 hours to complete this project. What you want to do isn't inherently complicated but there is a certain amount of learning you will have to do and knowledge you will have to aquire before you'll be able to do even the simplest things with PICs. I don't know how much research you've done on this so far so forgive me if you already know some of this stuff.

A PIC is essentially a miniature computer with certain built in capabilties that you control through software. It comes to you as a blank slate so you need to provide it with that software. The software needs to be written and then loaded onto the PIC by a device called a programmer. Programmers are inexpensive and are widely available. I bought one of mine off eBay for about $20. The software you load onto the PIC has to tell the PIC certain things before it does anything (i.e. which pins are inputs, which pins are outputs, the clock frequency, etc). If these parameters, or special function registers as they are more properly called, aren't set correctly the PIC might not function as expected. Once the software is written and loaded onto the PIC, it also needs a few external components to function in addition to the peripherals specific to your project. A power source, an oscillator, a few capacitors, etc. Just a PIC on it's own is useless.

If this is all news to you, I'd reccomend that you start by doing a search for "PIC tutotial". This one is pretty decent I thought:



but there are tons out there so you might find one that you like better.

You will also need some supplies (i.e. hardware) to start learning PICs. First you'll need a PIC, a power source, a programmer, some LEDs, and a solderless breadboard will come in very handy.

Don't get discouraged. There is a bit of a learning curve when first starting out with PICs but once you're past that you will quickly relaize how much you can do. There are people here who help you along the way if you get stuck. Good luck.