Function set for 4x20 LCD

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Hi ALL 8)

Does someone know the function set for a 4 x 20 LCD ?

ldi	temp, 0b00111000		;set as 2-line display,

This is what I see now (2x8):

01234567
89ABCDEF

This is what I have in memory.

ASCII: .db "0123456789ABCDEFGHIJ" ;20 ASCII characters

I must set as a four line ? But how ?

Thanks. 8)

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hi,

google for "how to use intelligent LCDs".
follow the first link, download lcd1.pdf & lcd2.pdf, read.
:)

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Here's two documents on the 44780 controller!

EDIT: Removed the attachment of Dmcman_full.zip (containing Dmcman_full.pdf). A copy of that PDF can be found here: http://www.avrfreaks.net/index.p...

Attachment(s): 

"He used to carry his guitar in a gunny sack, or sit beneath the tree by the railroad track. Oh the engineers would see him sitting in the shade, Strumming with the rhythm that the drivers made. People passing by, they would stop and say, "Oh, my, what that little country boy could play!" [Chuck Berry]

 

"Some questions have no answers."[C Baird] "There comes a point where the spoon-feeding has to stop and the independent thinking has to start." [C Lawson] "There are always ways to disagree, without being disagreeable."[E Weddington] "Words represent concepts. Use the wrong words, communicate the wrong concept." [J Morin] "Persistence only goes so far if you set yourself up for failure." [Kartman]

Last Edited: Wed. May 2, 2012 - 03:57 PM
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You should find that being a 4 line display there are two controllers in there, the lowest addressed controller will be used to control lines 1 and 3 while the highest lines 2 and 4.

Keep it simple it will not bite as hard

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sutton wrote:
You should find that being a 4 line display there are two controllers in there, the lowest addressed controller will be used to control lines 1 and 3 while the highest lines 2 and 4.

This was the problem. Thanks ALL ! 8)

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Hey RoB !

here it is if you haven`t it already:

 ldi     temp,0b00101000 ;set param:  20 char 4 line, 5x7 font 
 rcall   Lcd_cmd	;write funct. to Lcd

Ps: this is for a 2 controler display.

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Your Dmcman_full.zip doesn't unzip.

Hmm, my module's data doesn't include the pin spacing. It's tighter than .1 inch, maybe 2mm. Guess I'll figure on wires 'stead of pins or pads to match.

274,207,281-1 The largest known Mersenne Prime

Measure twice, cry, go back to the hardware store

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Quote:

Your Dmcman_full.zip doesn't unzip.


It probably died of old age.

And to answer the rhetorical question I posed at the end of your cross post. It is 7 times. One of them even by that same Johan bloke:

http://www.avrfreaks.net/index.p...

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I can't believe how much misinformation was spewed out in 2004. This one takes the cake:

Quote:
You should find that being a 4 line display there are two controllers in there, the lowest addressed controller will be used to control lines 1 and 3 while the highest lines 2 and 4.

And the reply is even more unbelievable.
Quote:
This was the problem. Thanks ALL !

Don

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Ah but there's been a lot of HD44780 water under the bridge in those 8 years. See my diatribe here:

http://www.avrfreaks.net/index.p...

(which includes the rhetorical question I ended up answering above).

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Quote:

Your Dmcman_full.zip doesn't unzip.

OK. I'll try to locate a fresh Dmcman_full.pdf and freshen the upload.

The "99rtd..." is the better one anyway, IMO.

Edit: The Dmcman_full "situation" has been resolved by a cunning manouvre known in The Interweb sub-culture as "linking".

"He used to carry his guitar in a gunny sack, or sit beneath the tree by the railroad track. Oh the engineers would see him sitting in the shade, Strumming with the rhythm that the drivers made. People passing by, they would stop and say, "Oh, my, what that little country boy could play!" [Chuck Berry]

 

"Some questions have no answers."[C Baird] "There comes a point where the spoon-feeding has to stop and the independent thinking has to start." [C Lawson] "There are always ways to disagree, without being disagreeable."[E Weddington] "Words represent concepts. Use the wrong words, communicate the wrong concept." [J Morin] "Persistence only goes so far if you set yourself up for failure." [Kartman]

Last Edited: Wed. May 2, 2012 - 03:59 PM
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Quote:

that same Johan bloke

Oh, that sad figure. Ignore him... :wink:

"He used to carry his guitar in a gunny sack, or sit beneath the tree by the railroad track. Oh the engineers would see him sitting in the shade, Strumming with the rhythm that the drivers made. People passing by, they would stop and say, "Oh, my, what that little country boy could play!" [Chuck Berry]

 

"Some questions have no answers."[C Baird] "There comes a point where the spoon-feeding has to stop and the independent thinking has to start." [C Lawson] "There are always ways to disagree, without being disagreeable."[E Weddington] "Words represent concepts. Use the wrong words, communicate the wrong concept." [J Morin] "Persistence only goes so far if you set yourself up for failure." [Kartman]

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Quote:

I can't believe how much misinformation was spewed out in 2004. This one takes the cake:
Quote:
You should find that being a 4 line display there are two controllers in there, the lowest addressed controller will be used to control lines 1 and 3 while the highest lines 2 and 4.


Remember that for 4-line -- "it depends". 4x40 certainly have two controllers IME. I seem to recall some smaller like the mentioned 4x20 also having two controllers. But a lot of character LCDs have passed over the aforementioned bridge over the past 10 years.

You can put lipstick on a pig, but it is still a pig.

I've never met a pig I didn't like, as long as you have some salt and pepper.

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Quote:
I seem to recall some smaller like the mentioned 4x20 also having two controllers.
The LCD controller chip (HD44780U or equivalent) has enough memory to deal with 80 characters but only has enough capability to display 16 of those characters.

To display more than 16 characters you need one or more auxiliary controllers (HD44100 or equivalent). Each auxiliary controller adds the capability to display an additional 16 characters. A 20x4 display will therefore have one controller and four auxiliary controllers.

With the advent of epoxy blobs to replace the ICs you may only have one blob for 2 or more auxiliary controllers.

Don