lcd and arduino uno

hello too all!

i have an Hitech Displays 16-Char LCD Panel HMC16202SG-LY-12-2 and i want to do the connection with arduino uno but i dont find the datasheet of this lcd ....

can anyone help me to find datasheet or knows for the pins ?

lcd :

thanks !

There's some numbers printed on the back of the display. I can only recognise nuber 16, which is on the right at that backside. That implies the numbering goes from 16 to 1 left to right from the front. But then again, i can also see a trace running from pin 2 to the backlight's cathode. And that contradicts the previous.

Maybe you have more luck looking for descriptions / datasheets of the honeywell alarm system they ripped this display from.

i find the backlight pins is 1 = + led and 2 = - led and use 12V for backlight because with 5V dosen't works..

but the other pins ? i search in google 1 day but nothing for this lcd..

That’s a garder variety display.
the wiring is available everywhere, including here:

I practically have it memorized. I copied the wiring illustration from the Sainsmart Nano Started Kit pdf
and pasted it into WORD for you.
There should be a link to download the library at the above link.

LCD WIRING.docx (315 KB)

I don't think you should have put +12V on pins 1 and 2. All the other parallel displays I have seen used 5V on pins 1 & 2. I hope you didn't damage it.

only with 12v the back light turn on with 5v don't work ! the Vcc ofcorse supply with 5v...

pin 1 = +12 v for led backlight pin 2 = -12V for led backlight i will check with multimeter and the led is turn on!!

i have no idea with the other pins if i use this schematic with don't know if the pin is true , i will damage the lcd ?

You need to get a second opinion from someone else on the forum. That is always recommended. I have seen many of the "4-bit" lcds and almost all of them with 16 pins use the same wiring I gave you. As I said, I am only one person , you should always wait until more than one person agrees on how to proceed. If the lcd is suppose to interface to +5V (TTL level logic) circuit, then all of the pins are can be connected to either +5V or ground. That is in the spec for TTL. The one thing that 'could' damage the lcd , but not necessarily is connecting the +5V power for the logic backwards (reversed), but actually most TTL ics can be plugged in backwards without damage. All the pins are INPUTS, which are HIGH Impedance by nature (or design actually). High Impedance inputs can be shorted to 5v or ground without damage. Outputs , not so. Shorting Outputs to ground can damage circuitry. Look for datasheet for your display and look at power supply voltages on datasheet. If it says +5V, it is probably wired like the drawing I gave you. But don't take my word for it. Get a second opinion, or third if possible. When all is said and done, it is your lcd and you must take responsibility for the consequences, not us.

You really have an orphan there! It is not a "garden variety". No datasheet to be found. I am presuming you obtained it from that website and that the picture fully matches - though if you did pay that price you really were ripped off badly.

The pin connections do not immediately correspond to the 1602 displays with which we are familiar. Pins 1 and 2 are indeed the backlight, but this circuit board provides for LEDs in series as well as parallel so that it may well require a higher voltage for them, possibly but not conclusively 12V. Measure the current draw.

It would appear from the photos that pins 3, 4 and 5 may be the ground, Vcc and contrast pins in the usual order, but I cannot see the traces quite clearly enough to be certain. The ground will generally be the one connected to the large areas on the pattern, while the contrast pin goes to a chain of five resistors. I am puzzled by the heavy traces on pins six and seven which seem to connect to the charge pump option area, but perhaps these do correspond in the usual order to RS and RW. It will not hurt to assume they function in the usual order and try it that way, given that the backlight pins have been added to the opposite end to usual.

See, that's why I told you to get a second opinion. I neglected to look at the photos. (I was going to look at them later).

See, that’s why I told you to get a second opinion. I neglected to look at the photos. (I was going to look at them later).

It’s quite a challenge trying to figure out things from poor photos on a dodgy website (re-loads every time I swap from one tab to another to look at it!)

Paul's right. That's an oddball and you paid too much for it. If I were you I would set it aside and until you can find someone online who got it working. In the meantime just get a cheap common lcd, like this one I just ordered: (serial AND parallel) ($4.23)

That's really the only suggestion I have for you right now.

thanks all for your help and your opinion but i damage the lcd ... dont worry i will buy a new 16x2 lcd 1602 and its play perfect ...

I'm sorry to hear it got damaged. We try to avoid that here and usually we're pretty lucky but at the end of the day you just have to take the good (what you learned from the experience) , with the bad . My parting word would be ," never buy anything on ebay that costs more than $5 without at least trying to get a second opinion on the price. Keep in mind that no matter where you live in the world, no matter what time it is, there is always someone somewhere else in the world who is awake and checking their email.

thanks all for your help and your opinion but i damage the lcd … dont worry i will buy a new 16x2 lcd 1602 and its play perfect …

But - what makes you think you have damaged it?

in fist use with the stadar schematic of 1602 the lcd start but make some crazy display ...

in the second boot after restart or unplug and plug again the lcd the lcd dont show nothink.. did you know if not damage ? can i tested ? but i dont know the datasheet i serche everywhere but nothing .. i send e-mail in the Hitech company but they dont reply me..

I know you realize it by now but when you buy something online first and look for the datasheet second you come to realize that perhaps it should occur the other way around. Now you know.

peiperakos: in first use with the standard schematic of 1602 the lcd start but make some crazy display ...

in the second boot after restart or unplug and plug again the lcd the lcd don't show nothing.. did you know if not damage ? can i tested ?

The question here is whether after re-wiring, you made some slight change which caused a different result.

The "test" would be to have it wired up correctly to start with. Since you have the display in question, which may or may not be precisely as in the illustrations, how about you take a really good fully-focused straight-on picture with your camera in "macro" mode and out in the noon sunlight so that exposure and field depth is perfect, of the display (both sides) and show them here so that we can follow the circuit traces and other details.

Beside this it my be as well to get one of the cheap displays with which most people here are familiar, and learn on that one before approaching the "problem" one. :D

peiperakos: but I don't know the datasheet I search everywhere but nothing

No, it's clearly an orphan.

peiperakos: .. I send e-mail in the Hitech company but they don't reply me..

Oh! What a surprise! XD

Good day I have some HMC16202SG-LY-12-1 and could find no data on them so I thought I will sacrifice one in the name of resiceling and got it to work not much different than the HD44780 ,look at the power lines mine is working in 4bit mode so I assume 8bit mode will work; pin 1-backlight +12v; pin 2-backlight -; pin 3-0v(ground); pin 4-Vcc(+5v);pin5-contrass pin 6-RS;pin 7-R/W; pin 8-E; pin 9-Data0----to------ pin 16-Data7.

12V sounds grossly excessive for the backlight.

Hello, the pinout of HMC16202SG-LY-12-1 is:

1 - +12V Backlight 2 - GND Backlight 3 - Vss 4 - Vcc 5V 5 - Vlc 6 - RS 7 - R/W 8 - E 9 - D0 10 - D1 11 - D2 12 - D3 13 - D4 15 - D6 16 - D7