16-bit counter pic16f877 problem

K

krpz

New Member

• Mar 10, 2013

• #1

I want to use the pic16f877 to count from 1 to 10000 so i need 2x 8 bit registers. I increment one of the register (the low part) in a loop and when i arrive to 0xFF i jump to another loop that increment one the high bit and then go back to low bit. But when the counter is in the 0x00FF the next number is 0x0100. Is there a way to change both of the registers in the same time because in my code first the low bit become 0x00 and then the high bit 0x01.

Thanks.

 

ronsimpson

Well-Known Member

Most Helpful Member

• Mar 10, 2013

• #2

loop:
..increment count_low
.....IF =00 then increment count_high (if carry bit =1 then inc. count_high)
.
.
.
go to Loop

 

Angry Badger

Member

• Mar 10, 2013

• #3

Hi,

Are you coding this in assembly or C?

 

K

krpz

New Member

• Mar 10, 2013

• #4

Sorry i forget to write this, ii am coding in assembly.

 

jpanhalt

Well-Known Member

Most Helpful Member

• Mar 10, 2013

• #5

Why not use TMR1?

John

 

K

krpz

New Member

• Mar 10, 2013

• #6

Thanks for the tip jpanhalt but i dont know how to do this, do you have in your mind a tutorial??

 

jpanhalt

Well-Known Member

Most Helpful Member

• Mar 10, 2013

• #7

You may want to look at my recent blog in which I use the lowly 12F683's 16-bit timer1 to count a 100Hz PWM signal. You want Zip_2.zip.

https://www.electro-tech-online.com/blogs/jpanhalt/254-memsic-inclinometer-assembly-language.html

John

 

K

krpz

New Member

• Mar 10, 2013

• #8

Thank you i am going to read it.

 

Last edited: Mar 10, 2013

House0Fwax

Member

• Mar 10, 2013

• #9

Have a look at Nigel's tutorial 3.2;