Re: LCD CODE


Mar 22, 2004

 


----------------------------

#5101 Mar 22, 2004

hai  This is pavan, for my project i need LCD code which i am using 8 bit interface. I need the algorithm how to write & if possible the code also.i am using PIC16F870 Microcontroller ,HI-Tech PIC C Compiler. Please help in this regard . I hope mail from u as soon as possible. i don't need any graphic LCD code. I just need simple LCD 8 bit mode code. byepavan

Win an evening with the Indian cricket captain:

Yahoo! India Promos.



----------------------------

#5104 Mar 23, 2004

I have code, but it is for 4 bit mode not 8.



I could let you have it, and you make the necessary alterations so

that it works in 8bit.



Is there any reason why you are using 8bit instead of 4?



Colin

--

cdb, bodgy1@... on 23/03/2004



I have always been a few Dendrites short of an Axon and believe me it

shows.



Light travels faster than sound. That's why some people appear bright

until they speak!



----------------------------

#5110 Mar 23, 2004

Nobody uses an 8-bit interface - too many IO pins are used up. The 4-

bit interface is actually easier to implement because of all of the 4-

bit example code out there to help you.



BRW



--- In piclist@yahoogroups.com, Pavan Kumar Vepuri pkvepuri80@y...>

wrote: > hai

>

> This is pavan, for my project i need LCD code which i am using 8

bit interface. I need the algorithm how to write & if possible the

code also.i am using PIC16F870 Microcontroller ,HI-Tech PIC C

Compiler. Please help in this regard . I hope mail from u as soon as

possible. i don't need any graphic LCD code. I just need simple LCD 8

bit mode code. >

> bye

> pavan

>

> Win an evening with the Indian cricket captain: Yahoo! India Promos.



----------------------------

#5114 Mar 23, 2004

you can also tie r/w to ground (write mode only) to save another

pin. thus the whole interface can be done with 6 pins which means

you can use 18 pin pics with an LCD display and actually have pins

left over to do some interesting things.

--- In piclist@yahoogroups.com, "Bennet Williams" bennet@e...> wrote:

> Nobody uses an 8-bit interface - too many IO pins are used up. The

4-

> bit interface is actually easier to implement because of all of the

4-

> bit example code out there to help you.

>

> BRW

>

> --- In piclist@yahoogroups.com, Pavan Kumar Vepuri

pkvepuri80@y...>

> wrote:

> > hai

> >

> > This is pavan, for my project i need LCD code which i am using 8

> bit interface. I need the algorithm how to write & if possible the

> code also.i am using PIC16F870 Microcontroller ,HI-Tech PIC C

> Compiler. Please help in this regard . I hope mail from u as soon

as

> possible. i don't need any graphic LCD code. I just need simple LCD

8

> bit mode code.

> >

> > bye

> > pavan

> >

> > Win an evening with the Indian cricket captain: Yahoo! India

Promos.



----------------------------

#5149 Mar 25, 2004

Respecterd sir  Thank u for ur response.  First let me know1.what is the advantage of going 4 Bit mode instead 8 Bit mode.2. I have pins left so only i am using 8 Bit mode. Sir if u had code for 4 bit mode please do send the code to my mail & if possible do write the algorithm for ur code so that @ fisrt i can understand ur code by reading ur algorithm Byepavan                           

cdb cdb@...> wrote:I have code, but it is for 4 bit mode not 8.

I could let you have it, and you make the necessary alterations so that it works in 8bit.

Is there any reason why you are using 8bit instead of 4?

Colin-- cdb, bodgy1@... on 23/03/2004

I have always been a few Dendrites short of an Axon and believe me it shows.

Light travels faster than sound. That's why some people appear bright until they speak!



to unsubscribe, go to www.yahoogroups.com and follow the instructions





Win an evening with the Indian cricket captain:

Yahoo! India Promos.



----------------------------

#5153 Mar 25, 2004

why use 4 data lines:

- saves 4 pins, maybe use a smaller PIC => cheaper PIC

- simpler to layout. especially since in most cases the pins are not

contiguous at the chip. this means a less complex board



why use 8 data lines:

- it is very slightly faster (really not worth considering)

- it is slightly less complex to implement (but again, not worth

considering)

- it looks like a cleaner design - nibbles are grubby in the comp sci

mindset. (hey, I got a degree in it, I'm allowed...)



You can find 4 and 8 bit source code in C and ASM all over the net.

Google is your friend.



Phil



--- In piclist@yahoogroups.com, Pavan Kumar Vepuri pkvepuri80@y...>

wrote: > Respecterd sir

>

> Thank u for ur response.

>

> First let me know

> 1.what is the advantage of going 4 Bit mode instead 8 Bit mode.

> 2. I have pins left so only i am using 8 Bit mode.

>

> Sir if u had code for 4 bit mode please do send the code to my mail

& > if possible do write the algorithm for ur code so that @ fisrt i

can understand ur code by reading ur algorithm >

> Bye

> pavan

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

>

> cdb cdb@b...> wrote:I have code, but it is for 4 bit mode not 8.

>

> I could let you have it, and you make the necessary alterations so

> that it works in 8bit.

>

> Is there any reason why you are using 8bit instead of 4?

>

> Colin

> --

> cdb, bodgy1@o... on 23/03/2004

>

> I have always been a few Dendrites short of an Axon and believe me

it > shows.

>

> Light travels faster than sound. That's why some people appear

bright > until they speak!

>

>

>

>

> to unsubscribe, go to www.yahoogroups.com and follow the

instructions >

>

>

---------------

> Yahoo! Groups Links

>

> To visit your group on the web, go to:

> groups.yahoo.com/group/piclist/

>

> To unsubscribe from this group, send an email to:

> piclist-unsubscribe@yahoogroups.com

>

> Your use of Yahoo! Groups is subject to the Yahoo! Terms of

Service. >

>

>

> Win an evening with the Indian cricket captain: Yahoo! India Promos.







----------------------------

#5156 Mar 26, 2004

Everything you ever wanted to know about HD44780-based character LCD

modules:



home.iae.nl/users/pouweha/lcd/lcd0.shtml



Another good technical resource:



www.geocities.com/dinceraydin/lcd/



Those should get you started. Good luck, study hard and learn.



Matt Pobursky

Maximum Performance Systems

On Fri, 26 Mar 2004 05:30:49 +0000 (GMT), Pavan Kumar Vepuri wrote:

>.Respecterd sir

>..

>..Thank u for ur response.

>..

>..First let me know

>.1.what is the advantage of going 4 Bit mode instead 8 Bit mode.

>.2. I have pins left so only i am using 8 Bit mode.

>..

>.Sir if u had code for 4 bit mode please do send the code to my mail &

>..if possible do write the algorithm for ur code so that @ fisrt i can understand ur code by reading ur algorithm



----------------------------

#5162 Mar 26, 2004

8 bit is considerably easier to implement. I recently made the

transistion to 4 bit to save I/O (as well as other reasons) and can

tell you it took me a lot of time to work it all out.



I would suggest that one starts with an 8 bit bus and move on from

there if appropriate.



Regards, John.





--- Phil phil1960us@...> wrote: > why use 4 data lines:

> - saves 4 pins, maybe use a smaller PIC => cheaper PIC

> - simpler to layout. especially since in most cases the pins are not

> contiguous at the chip. this means a less complex board

>

> why use 8 data lines:

> - it is very slightly faster (really not worth considering)

> - it is slightly less complex to implement (but again, not worth

> considering)

> - it looks like a cleaner design - nibbles are grubby in the comp sci

>

> mindset. (hey, I got a degree in it, I'm allowed...)

>

> You can find 4 and 8 bit source code in C and ASM all over the net.

> Google is your friend.

>

> Phil

>

> --- In piclist@yahoogroups.com, Pavan Kumar Vepuri pkvepuri80@y...>

> wrote:

> > Respecterd sir

> >

> > Thank u for ur response.

> >

> > First let me know

> > 1.what is the advantage of going 4 Bit mode instead 8 Bit mode.

> > 2. I have pins left so only i am using 8 Bit mode.

> >

> > Sir if u had code for 4 bit mode please do send the code to my mail

>

> &

> > if possible do write the algorithm for ur code so that @ fisrt i

> can understand ur code by reading ur algorithm

> >

> > Bye

> > pavan

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> >

> > cdb cdb@b...> wrote:I have code, but it is for 4 bit mode not 8.

> >

> > I could let you have it, and you make the necessary alterations so

> > that it works in 8bit.

> >

> > Is there any reason why you are using 8bit instead of 4?

> >

> > Colin

> > --

> > cdb, bodgy1@o... on 23/03/2004

> >

> > I have always been a few Dendrites short of an Axon and believe me

> it

> > shows.

> >

> > Light travels faster than sound. That's why some people appear

> bright

> > until they speak!

> >

> >

> >

> >

> > to unsubscribe, go to www.yahoogroups.com and follow the

> instructions

> >

> >

> >

---------------

> > Yahoo! Groups Links

> >

> > To visit your group on the web, go to:

> > groups.yahoo.com/group/piclist/

> >

> > To unsubscribe from this group, send an email to:

> > piclist-unsubscribe@yahoogroups.com

> >

> > Your use of Yahoo! Groups is subject to the Yahoo! Terms of

> Service.

> >

> >

> >

> > Win an evening with the Indian cricket captain: Yahoo! India

> Promos.

>

>





---------------

Do you Yahoo!?

Yahoo! Finance Tax Center - File online. File on time.

taxes.yahoo.com/filing.html



----------------------------

#5164 Mar 26, 2004

At 06:15 AM 3/26/2004 -0800, jrem wrote:

>8 bit is considerably easier to implement. I recently made the

>transistion to 4 bit to save I/O (as well as other reasons) and can

>tell you it took me a lot of time to work it all out.

>

>I would suggest that one starts with an 8 bit bus and move on from

>there if appropriate.



That's how I did it on the AVR. Got it working in 8 bit, then converted to 4 bit.



MAKE SURE that you keep the timing constraints on the 44780 spec.

Most of the problems that I hit, were in timing, and not EXACTLY following their init sequence. It's pretty picky about that, and the only symptom you'll likely get is "no display".







----------------------------

#5173 Mar 26, 2004

--- In piclist@yahoogroups.com, David VanHorn dvanhorn@c...> wrote: > At 06:15 AM 3/26/2004 -0800, jrem wrote:

>

> >8 bit is considerably easier to implement. I recently made the

> >transistion to 4 bit to save I/O (as well as other reasons) and

can > >tell you it took me a lot of time to work it all out.

> >

> >I would suggest that one starts with an 8 bit bus and move on from

> >there if appropriate.

>

> That's how I did it on the AVR. Got it working in 8 bit, then

converted to 4 bit. >

> MAKE SURE that you keep the timing constraints on the 44780 spec.

> Most of the problems that I hit, were in timing, and not EXACTLY

following their init sequence. It's pretty picky about that, and

the only symptom you'll likely get is "no display".



yeah, the whacky thing in 4 bit mode is hitting the controller three

times with the init sequence, I would have never figured that out

without searching for examples. Timing works great if you do a busy

flag check after device initiation, it's not that hard, I don't know

why so many folks avoid it for delay routines.


S
e
n
i
o
r
T
u
b
e
.
o
r
g