Hi there,

I need to do a counter using the PIC 16F84A so that when one switch is pressed the counter will increment and when the other switch is pressed the counter will decrement. The count is from zero to 999. What i need is this, when you press a switch (increment or decrement) the counter will increment or decrement. if you press it and hold it the counter should increment or decrement, the problem here is the counter should increment or decrement with some speed. when you press one time it will increment or decrement by 1. in this case the counter increment or decrement by 1 but wqith some speed. But numbers should display with out skipping.

Anybody knows the coding?? Thanks

 

Is this a homework assignment?

 

No this is a second year project. We have drawn the circuit diagrams using logic icus and now we are devoloping it using pics. Some parts we don't know how to do it pic. If you can pls help i will send you the scanned 4toz of the circuits.

 

How is a Second year school project no a school project? Isn't it expected by your instructors that you come up with the design yourselves?

 

Wow, thanks to you he will learn nothing about how to do this project. I wouldn't call that helping...

 

Im in a university. We develog this counter using logic ics for 1st year electronic engineering ii. Now we are redevoloping it using pics for second year subject call embedded system design. Cn u help us?

 

You just had it handed to you by Alberto, what else do you need?

 

Thanks. I will send the images of the circuits tomorrow. There is another problem with this pic. We have 3-4 circuits for this project. we convert to circuits by using pic. when we convert circuits give us 20 output lines. but we had 24 output lines with using logic circuits. now cannot connect these two circuits.(pic circuit and not converted circuit). we dont know how to convert that circuit.

 

Why not use a PIC with enough I/O to do what you want rather than add all sorts of Glue logic?

 

I forgot to tell this. we are using two sensors in this. increment and decrement happens according to this. sorry. you will get a clear understand when i upload the pictures of this.

 

What language are you going to program it in? ASM? C? BASIC? JAL?...

 

We will use asm.

 

Try not to use the ancient 16F84 it's modern, better and cheaper replacements are the 16F628A and 16F88

 

I can recommend Matrix Multimedia's tutorial CDROMs; Assembly for PIC Micro and C for PIC Micro. You can also buy a development board which will simplify things for you but you can get by without it. The tutorial CDROMs cover all aspects of basic-level programming for PIC Micros and will no doubt cover the subject area you refer to.

http://www.matrixmultimedia.com/product.php?Prod=C for PICs and Dev board S/O

Your second year project is pretty basic stuff I have to say. If you do decide to go through Matrix Multimedia's tutorial work, then you will definitely gain enough knowledge to complete your project.

Brian