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How to connect LCD at MSP-EXP430G2 ?


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Hey. I have got MSP-EXP430G2 LaunchPad and LCD screen.

 

I was trying to connect LCD to MSP-EXP430G2 but with no good result :?

 

I don't know what wrong did i do while connecting it...

Do I have to use any outside reinforcement for LCD ?

Could you possible to tell me what kind of pins from LCD (by numbers) connect to MSP-EXP430G2 pins (by numbers) ?

 

I connect it by cables - I mean lcd_pin->cable->launchpad_pin).

 

My LCD is:

LCD-AC-0802E-DIG G/KK-E6 C

- 2x8, 58x30mm

- LED

- extended temperature range 3V, "fast" 1-LED 20mA PURE GREEN cyrylica

Datasheet of this lcd is added as attachment to topic.

 

 

 

 

 

I am new with this kind of stuff and I have got some problems, I hope you will be able to help me, thanks! ;)

post-9998-135135528719_thumb.jpg

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your datasheet is not a datasheet, did not tell electrical and timing conditions.

 

are u sure u got a 3.3v module?

 

i had one w/ the exact same layout / size but different p/n from ebay and they are 5v.

 

did u use tested code (may be works for other lcd module) to try this one out.

 

are u in a position to use a "good" lcd to try out your code?

 

. try apply 3v to your A/K (back-light led) and see if it lights up.

. when u apply power to the supply pins, do u see a contrast change on the dots of the lcd? my will show a contrast change on "one" of the two lines.

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To help you, we need a datasheet, which as simpleavr states will help us help you. Claiming the above posts as useless is immature(I think it's more of a language barrier). We need more information from you.

 

Anyway.. where did you get this LCD from?

Does it look like the one in this thread?

 

More on the connections here.

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@rumikumi

 

there is nothing we can do to help u as there is not enough information.

 

i had suggested simple diagnosis that will enable us to start solving the mystery. u can let us know the result and we can work from there.

 

. if you supply 3v-5v to led back-light, did it light up?

. when u supply power Vss/Vdd etc to the module itself, did u see contrast change (i.e. all dot shows a level of gray) ?

. does your hook-up contains also a trimmer (variable resistor) to control contrast, if so, did u try to alter that and see (all dark or all white dots during power up)?

 

 

i would think the most important piece is to make sure your module is 3.3v. i cannot find any datasheet based on the model number u provided. are there any other "brand name", "part numbers" printed on the module itself. if u can take a picture on the back side (or a drawing) that might help. it is important to get any "wordings" that we can search.

 

also, a typical lcd module will have a resistor ladder (a row of resistors) for building up Vop for the LCD bias, if u can take a picture that can show the values there, it can let us guesstimate whether it's a 3v or 5v module.

 

the following article shows how a resistor change can affect it's operating range (3v / 5v)

 

http://dangerousprototypes.com/2011/11/ ... g-on-3-3v/

 

there may also be connection errors, u can double check or show us (schematic / photo) how u hold up via "cables" and we can recommend tests.

 

:)

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First of all thanks for all replays!

 

Here you can see how my LCD looks like: http://imageshack.us/g/856/20111216154652.jpg/

 

At back of LCD there is a label with note:

CBC008002E09-DIG-R

LOT:M1012226

DATE:20110217

 

I was googling for "CBC008002E09-DIG-R" phrase and I have found 1 auction with "my LCD", here it is http://www.ebay.pl/itm/ART-New-LCD-2x8- ... 0763803322

 

Quote from auction:

 

New LCD 0802 display with LED (pureGREEN) NEGATIVE (Double FSTN)

LCD-AC-0802E-DIG G/KK-E6 C PBF

Extended TEMPERATURE range (-20+70deg.C)

NEW - FOIL. Controller : HD44780.

 

High Quality LCD Module

Producer : AV-DISPLAY

 

Datasheet there is same as I have... :P

 

I have checked

 

I would like to write that i have a small experience with programming HD44780 lcd - i was using my friend lcd at summer but now he is far away and we dont have conntact.

 

 

. if you supply 3v-5v to led back-light, did it light up?

No. I connect it to launchpad: pin1 to Vss and pin2 to GND and there nothing happens at screen

 

. when u supply power Vss/Vdd etc to the module itself, did u see contrast change (i.e. all dot shows a level of gray) ?

nothing happens

 

. does your hook-up contains also a trimmer (variable resistor) to control contrast, if so, did u try to alter that and see (all dark or all white dots during power up)?

i can't anwser it - i dont understand it

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LCD-AC-0802E-DIG G/KK-E6 C PBF

i found these two links

 

http://system-one.blogspot.com/2011/02/ ... g-and.html

this one is from the same series but not is a different variety (different black light) and it's 5v.

 

http://www.kamami.pl/index.php?categoryID=73

this link indicates they are of a same series of devices but there is no indication whether it's 3v or 5v.

 

i suspect it's a 5v device.

 

No. I connect it to launchpad: pin1 to Vss and pin2 to GND and there nothing happens at screen

Vss is ground, pin2 should be Vcc and u connect that to + positive voltage. please reverse and try again.

 

 

. does your hook-up contains also a trimmer (variable resistor) to control contrast, if so, did u try to alter that and see (all dark or all white dots during power up)?

 

you could try the following setup, via breadboard + jumpers, etc.

 


                   +------------+------o +3v / +5v
                   |            |
                   | 14 13      |
                   |  o o       |
                   |  o o       |
                   |  o o       |
                   |  o o      .-.
                   |  o o      | |
                   |  o o----->| | 5k/10k pot
 pin 1 Vss/Gnd     +--o o---+  | |
     2 Vdd            2 1   |  ,_,
     3 V0 (lcd)             |   |
                            |   |
                            +---+------o Ground / 0v
                                |
                               ___
                               ///

 

u could 1st try to apply 3v

turn the pot to one side 1st

apply 3v, see if dots shows up or not

if not, turn the pot all the way to the other end and apply 3v.

see if dots shows up or not

 

if u see nothing, try and use 5v, turn the pot both way and see.

if the lcd is operational, u will see darkened dots.

 

u need to verify u have a working lcd module 1st.

 

also for the led back-light, the power is not through the header, they are on the other end and label A and K (cathode, anode), u can apply 3v-5v (briefly) to see if they lights up.

 

if u have a 5v device, you will need extra circuitry to make it work w/ the launchpad.

 

i cannot make out much from your photo.

 

look carefully on the resistor values on the pcb. u should find 5 resistors that have the same value (2.2k / 222), they form the lcd voltage divider / bias voltage, along w/ another one which usually is 91k / 913 or 75k / 753, if it's 91k its most likely a 5v device, if it's 75k it's 3v.

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your 1st goal is to achieve this

 

viewtopic.php?p=14511#p14500

 

notice the photo that one line has the dots darkened. it tells us that the lcd module is good, but the mcu failed to talk to it yet.

 

otoh, if u don't see a thing, it could be

 

a) lcd module faulty.

B) lcd module not getting the power it needs (or incorrect voltage).

c) everything is actually working but u can't see it because the contrast is too light.

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Here is my sample code:

 

#include "msp430x22x4.h"

void Delayms(int n){
  do __delay_cycles(10000); while(--n);
}

void _E(void)
{
 P2OUT |= BIT6;  // toggle E for LCD
 Delayms(1000);
 P2OUT &= ~BIT6;
}

void main(void) 
{
while(1)
{
 P2SEL = 0;
 P2OUT = 0; 
 P2DIR = ~BIT0;
 P2OUT &= ~BIT4; //clear P2OUT , RS
 _E();
}
}

 

 

For test i connect only 5 cables:

 

P1N1 from LCD to GND

P1N2 from LCD to VCC

P1N4 from LCD to P2.0 // RS

P1N5 from LCD to P2.1 // R/W

P1N6 from LCD to P2.2 // E

 

as datasheet says download/file.php?id=1419

 

With that simple work no effect on LCD, why ?

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