hey all,
new 2 this forum.
I need help with my school project. I'm supposed 2 build a timer for varying between 0-80 mins. My teacher suggested to me using a programmable PIC chip. What the hell is a PIC chip? Can someone give me websites?

the timer is an astable timer which turns on a LED for 10 seconds after a certain charging time? Im not sure how I could use the PIC chip to carry out this task? anyone kno? hlp!

 

A PIC is a microcontroller. Microcontollers are an entire computer( memory, CPU, storage space, timers, etc.) crammed into a single chip. MOst low cost microcontrollers cost between $2 and $10 depending on what features they have.

Microchip.com is the website for the company that makes the PIC. Other Microcontrollers to look at are the AVR made by Atmel, the Z8Encore made by Zilog and the 8051 which is made by a lot of companies (Silicon labs has my favorite though silabs.com).

I'd recommend buying a development kit for which ever one you choose - it will save you a lot of headaches and thay arn't that expensive. Z8F08200100KIT (the Z8Encore) is $39 on digikey.com I've heard its a great kit. ATSTK500 (the AVR) is also a good kit though it can be a pain to get started (also available on digikey.com). The ASTK500 also works as a device programmer which is nice.

Hope this helps
Brent

 

the PIC is a microcontroller. The manufacturers website is www.microchip.com. I am certain there are several PIC based timer references available on the internet.

 

thanx 4 the info but how could I get my project to work without buyin a electronics set...i think my teacher will suspect somethin.

 

i need the timer to be an astable timer which turns on a LED for 10 seconds after a certain charging time (0-80 mins)? Would the PIC chip definitely work for this circuit?

 

You could use a PIC to replace most timers, certainly it will 'wipe the floor' with a simple astable. With suitable programming you could use a PIC as a timer for almost any time you want - micro-seconds to millions of years, as high as you can imagine really (although testing takes a long time :P )

As this was suggested by your teacher, I would expect programming facilities and chips are available in your school.

 

A PIC would work for this circuit.

An Astable timer cannot have a charging time as long as 80min. There arn't capacitors with the right characteristics to make a circuit like that work.

You could use counter chips to get a specific delay but if you want to have a programable delay a Microcontroller is an easier solution.

 

Here is an example of an advanced programable timer: http://www2.turbokeu.com/myprojects/countdown3.htm
more about pics: http://www.interq.or.jp/japan/se-inoue/e_pic.htm

 

if you're teacher suggested that you use a PIC I think he/she expects you to buy a kit. The only other way to do something with a microcontroller is to make your own kit. While not very difficult, it is well more advanced that lighting an LED.

I REALLY like AVR's but to be honest I don't have much experience with any other microcontroller. I have an STK500 sitting on my desk right now, they're rather expensive as far as development kits go especially if you doubly the cost by getting one or more of the add on cards for it. One of them is the STK502, got a LCD display built right into it I'm gonna go look at the spec sheet at it now.

Go for a PIC. They're extremely common and you can easily get help for them.

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