Help me with choosing a suitable PIC

[l_hui]

choosing a suitable PIC

hihi..

In order to make MCU less burden, i m connecting a PIC between the 4X4 keypad n MCU.. Bt the problem nw is wat is the suitable PIC that i can use to connect?

A PIC16f877 or a PIC16f876?

What is the differences between them? Do they produce a big effect to the MCU?
Wat is the function of the ports of PIC16f876 and PIC16f877?

Nex, i wander when the 4X4 keypad is pressed, wat is being sending into the PIC?

Izit a signal that show input high or low?

Then wat is being sending out from the PIC to MCU? Izit a digital output or else?

 

[cool.man]

Re: choosing a suitable PIC

In order to make MCU less burden, i m connecting a PIC between the 4X4 keypad n MCU

Unable to understand what does it mean,
Are you using two microcontroller.
Is it like that one controller is connected to keypad,After reading data from keypad 1st microcontroller sends data to 2nd microcontroller.
Clarify your scheme.

 

[l_hui]

Re: choosing a suitable PIC

Ya.. Is lik ur understanding.. Can u please explain wat u knw using the two microcontroller..

 

[pranam77]

choosing a suitable PIC

There is nothing like "burden" on a microcontroller. You can ulitise all its ports and still expect it to work at its full efficiency provided it is powered and used in its temperature limits. Anyways, if you mention about what is your project, you may get better sugessions. On the basis on what you have mentioned, and what i understood, you may choose PIC16F628 OR PIC16F877 for your application.
Cheers

 

[Kurenai_ryu]

choosing a suitable PIC

876 - 28 pin
877 - 40 pin
628 - 18 pin
(from my memory, check the datsheets for accurated info!)

if 'ts JUST for a 4x4 keypad, i would go for the 628... i need 8 pin to connect the keypad an can use the internal UART to send the keystrokes... that's 2 pin more (1 if you don't need an ack) 2 pin power supply 2 pin crystal (or use the internal oscillator) and 1 pin for MCLR (tied to vcc by a 10k resistor) I have 2 pin for extra fun!.. having it SMD it will be a ninja on the pcb...

with a bigger PIC, i'll end with many unused pins...

 

[yChien]

choosing a suitable PIC

Hi

me n my frens are trying to learn sumthing new on our own n we faced quite alot of problem since we r new to wut we try to approach...

we r trying to learn how to key in data via a pic to MCU den show it on a LCD...

What if the choice is between a pic16f877a and a pic16f84?
we r trying to place a pic between the 4X4 alphanumeric keypad and the MCU which is quite similar with what l_hui asked earlier...

N we are also new to the programming pic part...


p./s.: Sorry for the broken english which might cause u guys hard to understand my question...

 

[cool.man]

Re: choosing a suitable PIC

l_hui :
If your 2nd microcontroller have enough pins left then you can directly interface keypad with it.No need of PIC controller.
which 2nd microcontroller you are using?

yChien :
As you are beginner what you do is, try to interface keypad with pic microcontroller only.Also connect some leds on the pins of controller.When a certain key press light up certain led.when you do this then connect an LCD with microcontroller (print something when a certain key is press) instead of Led's.
This would be easier for u to understand.
Then you go for a 2nd microcontroller.

 

[yChien]

choosing a suitable PIC

oic... thanx for the advice~~

erm.. any nice web page which i can learn how to program a pic16??

Thanks for the help..

 

[numa]

Re: choosing a suitable PIC

here you go

**broken link removed**

Old but still useful http://www.rentron.com/Myke3.htm