Discussion in "Electronics" started by    amsams    Sep 10, 2014.
Wed Sep 10 2014, 07:24 AM
Hi Everyone,
Its been like more than 3 years I'ven't been logging into the forum. I'm really sorry not to signing in often. Anyways now I finally logged in to put a question on electronic musical instrument like the digital keyboard from Xin Yun and the model no. is XY-213 54 keys keyboard.
Well it was good when i played it for long. But when I used the battery with required supply of voltage with AA batteries, I got the LCD panel dimming out often. And with time the display on the panel completely went off that you can't notice anything on it other than its engraved inside ones and the glowing of backlight LED . So I've opened the screws inside and checked whether the connections were lose. But they are all intact. I even resoldered every pins under the PCB. But it didn't help. So I wonder the LCD panel is not properly pressed or something, opened the LCD board and cleaned out the carbon contacts. I found it has pins like RD, CS, WR, DATA, VSS, VDD, +, and 2 other pins for LED terminals. Well it didn't help even after pressing the LCD screen properly. Nothing was displaying on the screen. Hence I tried to find the datasheet of that LCD which is HT1622-v2. I thought v2 means version 2 but I could only get the datasheet for just HT1622 which mentioned the max supply voltage that can be provided to LCD is 5.25V. Therefore I measured the supply voltage to the LCD in the when I turned ON the keyboard found to be 6.29V. For seconds, I thought wow it must be the culprit that might have been preventing LCD not to display any visible data. So my question is... Is the LCD really dead due to the high voltage supplied in it? And is there any way to repair it without changing to new one. And how would i check that LCD is really dead or not? I've attached some pictures of it like when i press slightly the data get displayed. So guys recommend me how to find the fault in the PCB/components.
Wed Sep 10 2014, 07:27 AM
The pictures of the LCD....

Wed Sep 10 2014, 08:01 PM
As the data comes on if you press the glass you have
bad connections to the black connectors.
I have not had much luck with these, but you might do better .

Try removing the glass and repositioning the strips to make contact.
If that fails try gently cleaning the connections between rubber and glass
and rubber and pcb.

[ Edited Wed Sep 10 2014, 08:08 PM ]
Thu Sep 11 2014, 04:09 AM
Dear ExperimenterUK,
Thank you for the advice. Anyways I did clean the area you told. Well actually when I unscrewed the LCD PCB the screen and the rubber were intact with both the PCB and the screen that it doesn't fall off when you lift the PCB upside down. So I assumed nothing is wrong with those connections. Though I have disconnected the connection between rubber wire and the LCD PCB and cleaned it. But its not working. And please make sure that when you press quiet slightly at the edge of the screen, some data are displayed. If you press on the edge firmly, not even a single data is displayed. Looking forward for the further reply......

Get Social


Powered by e107 Forum System


Thu Nov 21 2019, 12:30 PM
how to interface 8051 microcontroller with NRF24L01+ module
Sat Oct 12 2019, 10:23 PM
Log in.. then post your code in the 8051 forum
Sat Oct 12 2019, 10:18 AM
Bhadra Sajikumar
i am doing a countdown timer with 8051 for my project, unfortunately our professor had to take a leave of absence before he could teach us most of it.. can someone explain the .asm code of it for me?
Mon Sep 23 2019, 07:37 AM
I am doing a project for my schools wireless security system with cameras,sensors and spot lights using 8051 micro controller, could you help me out with the design and its source code.
Wed Sep 18 2019, 08:48 PM
Caryn Kover
Thank you for your time,
Mon Aug 05 2019, 07:09 PM
@Ismail ..post in forum, give details
Mon Aug 05 2019, 04:33 PM
Ismail balghmi
Hello. Please I won't download
Wed Jul 24 2019, 12:47 AM
@BUSTER123 Please post in the forum
Tue Jul 23 2019, 06:13 PM
hello! newbie here. i am kind of a guy who hates using ready - made existing libraries, so this helped a lot as i was trying to control and write to a character lcd display. however, i can't figure out how to set the cursor position. for example, i want to set it to the 5th column in the first row, so position 5. so according to the table, i am sending 10000101 on the 8 data lines of the lcd (register select pulled low). the cursor does not move there however. and i cant move the cursor left or right too. is it something wrong that i am doing? thank you.
Thu Jul 11 2019, 07:55 PM
@ramos https://www.theengineeringprojects.com/2017/09/l298-motor-driver-library-proteus.html



Tue Dec 03 2019, 07:53 AM
Mon Nov 25 2019, 08:25 PM
Tue Nov 19 2019, 03:13 PM
Mon Nov 18 2019, 11:00 AM
Wed Nov 13 2019, 06:25 AM
Mon Nov 11 2019, 01:31 PM
Sun Nov 10 2019, 04:42 AM
Sat Nov 09 2019, 03:41 PM


Guests: 41, Members: 0 ...

most ever online: 182184
(Members: , Guests: 182184) on 06 Aug 2010: 05:37 AM

Members: 38107
Newest member: ananyagupta
Forum Activity
ExperimenterUK Avatar
Posted By ExperimenterUK
Fri Nov 29 2019, 04:24 AM
" Is it possible to interface a fingerprint scanne...
ilylily07 Avatar
Posted By ilylily07
Thu Nov 28 2019, 03:50 PM
You will not find any code for an 8051 as no one w...
ExperimenterUK Avatar
Posted By ExperimenterUK
Tue Nov 26 2019, 05:44 PM
You will not find any code for an 8051 as no one w...
ilylily07 Avatar
Posted By ilylily07
Tue Nov 26 2019, 04:13 AM
I tracked down a OV7670 data sheet.The OV7670 puts...
ExperimenterUK Avatar
Posted By ExperimenterUK
Tue Nov 26 2019, 12:08 AM
I tracked down a OV7670 data sheet.The OV7670 puts...
ilylily07 Avatar
Posted By ilylily07
Mon Nov 25 2019, 04:38 PM
The 8051 has too little memory to do anything us...
ExperimenterUK Avatar
Posted By ExperimenterUK
Tue Nov 19 2019, 10:44 PM
The 8051 has too little memory to do anything us...
ilylily07 Avatar
Posted By ilylily07
Mon Nov 18 2019, 09:54 AM
0v7670 camera interfacing with stc 8051.using asse...
Jeanbusatta Avatar
Posted By Jeanbusatta
Sun Nov 10 2019, 04:43 AM
ty, really needed it
ExperimenterUK Avatar
Posted By ExperimenterUK
Tue Oct 22 2019, 05:18 AM