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PCD8544 (Nokia LCD)
http://forum.lcdinfo.com/viewtopic.php?f=14&t=474
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Author:  Henri [ Sat May 15, 2004 14:25 ]
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The one here is the only "supported" connection method as that's the only one I've tested with. Of course other ways to connect can work fine too.
There are two chips that can be substituted in the schematic and they are 74LCX245 and 74LVC245. I know there are also other ICs that provide the same functionality but I don't have any names to give now. Basically you need an IC that tolerates 5V levels in it's inputs and gives out 2.7V - 3.3V levels.

Author:  DonFranczesko [ Sat May 15, 2004 14:58 ]
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Hmmm.... I see, that there is LP2950 so I can also use another controller which gives 3.3 V form 5V, right?
And 74LCX245 or 74LVC245. I understand that this is requied for LCD to works with all lines (lpt1-6) which are powered by 5V and must be converted to 3.3V?
I suppose that I don`t understand whats 74LCX245 or 74LVC245 for :) Becouse I see that LPT7 is at 3.3 V after this chip. So for example can I use several of this chips LP2950 (or others with the same function) 6 precisly :) and connect them to all LPT lines (one chip for one lpt signal)?

Author:  DonFranczesko [ Sun May 16, 2004 11:21 ]
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I found 74LCX245 in the store. But I can`t find LP2950. I found only LP2950C2-3.0 which parameters are: [V] 3,0 [A]0,1 case TO92 [Drop
out volt.]0,45 [V] is this is good? How many [A] does LCD from Nokia 3310 absorb? And is there too big drop out at the LP2950? 0,45 Gives about 2,6V at the end. I can also use a LP2950CZ-5, which is a stabilizer of 5V and add a resistor, what do you think?

Author:  Henri [ Tue May 18, 2004 17:30 ]
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LP2950C2-3.0 should be fine based on the info you gave. The one I used was something like LP2950-3.3 which was 3.3v 100mA version in SMD package. But 3.0v version is just fine.

Author:  DonFranczesko [ Tue May 18, 2004 20:39 ]
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So its ok... good :)

I will do construct this circuit soon.

Oh, and one more question. In data sheet of controller to nokia 3310 LCD there are shown commands for ex. to turn on LCD test (whole screen goes black). Is there a program to change the LPT signals from low to high and than inversely(only this requied pins)? Or maybe you have tutorial for Visual Basic to control LPT port? I only want to send to the LCD one byte, but do I also must change some signals to low? If its hard do to that kind of progam just say it ;)
And can I after 74LCX245 signals out connect LEDs (one for a one line) to see what signal is on it now (low- led is off, high led is on) or if this IC will be overloaded?

Author:  rekked [ Sat May 22, 2004 0:01 ]
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Hi:

Here, at www.hardcore-modding.com (spanish modding community) we have just discovered all the stuff concerning Nokia LCD screens. Some of us have made the 3310 work, but we're still having problems with 5110.

I just opened the phone, and took the LCD + PCB board (so it is easier to weld later), but I don't know which cable is what. Could you help me out?

This are some images:

(FRONT)
http://www.imagedump.com/index.cgi?pick=get&tp=75085

(BACK)
http://www.imagedump.com/index.cgi?pick=get&tp=75087

I can see the 9 pin holes, and I've labeled them a-i. Could somone match them to 1-9, please?

Author:  Henri [ Sat May 22, 2004 17:24 ]
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DonFranczesko wrote:
Is there a program to change the LPT signals from low to high and than inversely(only this requied pins)?
Or maybe you have tutorial for Visual Basic to control LPT port? I only want to send to the LCD one byte, but do I also must change some signals to low? If its hard do to that kind of progam just say it ;)

I know there are programs that allow you to toggle the pins but don't remember names at the moment. Not helping that much but at least you know that they exist. ;)
But to control the display by just toggling the pins is too much work I think. You need to do lots of toggling and probably make a mistake somewhere and also some timing critical parts might not work this way. Better solution would be to write a simple program to control the LPT port pins and then put the wanted sequences in the program code.

Here was some discussion about controlling LPT port:
http://www.skippari.net/phpBB2/viewtopic.php?t=78

Quote:
And can I after 74LCX245 signals out connect LEDs (one for a one line) to see what signal is on it now (low- led is off, high led is on) or if this IC will be overloaded?

I don't remember now how many mA's the IC can source but I think it's enough to light a led. But adding something to the signal lines might cause undesided effects. Or maybe not.

Author:  Henri [ Sat May 22, 2004 17:27 ]
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rekked wrote:
I just opened the phone, and took the LCD + PCB board (so it is easier to weld later), but I don't know which cable is what. Could you help me out?

I can see the 9 pin holes, and I've labeled them a-i. Could somone match them to 1-9, please?

The pinout for the 5110 display should be the 9 pin pinout at the first page. I don't know which side is pin 1 but google should help you with that.

Author:  DonFranczesko [ Sat May 22, 2004 19:38 ]
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Generally, thanks a lot for helping me! :)

Quote:
I don't remember now how many mA's the IC can source but I think it's enough to light a led. But adding something to the signal lines might cause undesided effects. Or maybe not.


Recently I have thought about it. I think about doing a small circuit:

pin----+------LED green-------------+
|||||||+--inventer---LED red--------+GND

+ is a ramification

and so on for other pins. What do you think? Will it work?

And BTW- how many mA does LPT port provide?

ps. And thx again :)

Author:  Henri [ Tue May 25, 2004 17:01 ]
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Some of the discussion not about LCDInfo was moved to the appropriate forum:
http://www.skippari.net/phpBB2/viewtopic.php?t=674

I should do more cleaning in this topic sometime later.

Author:  Henri [ Tue May 25, 2004 17:05 ]
Post subject: 

DonFranczesko wrote:
Recently I have thought about it. I think about doing a small circuit:

pin----+------LED green-------------+
|||||||+--inventer---LED red--------+GND

+ is a ramification

and so on for other pins. What do you think? Will it work?

Hmm, I didn't quite get this. Maybe you would like to try making more clear drawing of this.

Quote:
And BTW- how many mA does LPT port provide?

That depends of the LPT port. Some can source more, some less. Only few mA generally should be expected I think.

Author:  Ippe- [ Tue May 25, 2004 22:19 ]
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Hmm.
hope I have got this right. :)
So is it ok if I replace 74LCX245 with http://www-s.ti.com/sc/ds/sn74lvc245a.pdf?

Author:  DonFranczesko [ Wed May 26, 2004 20:34 ]
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Henri wrote:
DonFranczesko wrote:
(...)and so on for other pins. What do you think? Will it work?

Hmm, I didn't quite get this. Maybe you would like to try making more clear drawing of this.


I made more clear drawing of this circuit :) It is under this link

I draw on this scheme IC 7404, but not the whole integrated circuit, but only one gate from it (for one pin from LPT),
including Vcc and Gnd pin of the 7404.
Of course the Vcc and Gnd I can take from external power source, like molex plug (if its needed) :)


I have few questions about it:

1. Do you think it will work? (like I said earlier :) )

2. Does LPT port will provide such a power (mA) to power this leds (two for one pin) or maybe the IC also?

Does every pin from LPT provides separate stream (mA)?

And the last question - can I after this plug LCD from Nokia? :) Or will it be too much? :)

Author:  inanc_gangster [ Sat May 29, 2004 12:12 ]
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hi

I am here new.
I have nokia 3310 lcd already connected on the
lpt port.

but I have no software

which programme use you?

greetz,

me

Author:  Henri [ Tue Jun 01, 2004 0:24 ]
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Ippe-:
Yes, you can use 74LVC245 instead of 74LCX245.

DonFranczesko:
I think what you draw could work but I only quickly looked at it. Of course you'll get the definitive answer when you try it. ;)

About the LPT power sourcing capabilities, I don't think you should expect much but you might get surprisingly much. Very vague, I know, but you only know when you test it. I think this can vary a lot between motherboards.

I can only say that the connection I presented on the first page worked for me but I can't give any promises that it works for everyone else or that it would work after modifications. It's up to you to test. ;)
And after testing you could report what happens and then we all would know slightly more.

inanc_gangster:
How about LCDInfo ?

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