character lcd - HD44780 16x2 LCD does not work properly

Currently writing a program for ATmega32 MCU and I'm having issues with LCD not working. Tested with several ATmega32 MCUs as well as with several HD44780 compatible LCD modules (one of them is DEM 16216 SGH http://www.csd-electronics.de/data/pdf/DEM16216SGH.pdf )Tested with init method described in datasheet as well as current one. Screen turns blank after init (or shows blocks if contrast is adjusted) and nothing else happens.ATmega32 is running on internal 1MHz clock5V power supplyPORTC pins are connected to data ports of LCD (PC0-DB0...PC7-...Read more

character lcd - Is heat slowly killing my 20 x 4 LCD?

I'm using a QC2004A 20 x 4 LCD (blue back ground/white text) with a PCF8574 I2C backpack in a GPS trip logger. I leave the trip logger in the car. When I start the car, the trip logger starts automatically. Everything works fine except on days when the car is hot inside. When first started up the LCD is all white (like if the contrast potentiometer is set incorrectly). As the A/C cools the inside of the car, the LCD returns to normal.Is this heat slowly killing the LCD or will the LCD be OK?The QC2004A data sheet I have shows:Operating Temperat...Read more

character lcd - LCD 16x2 can't display

I have a small project with AT89S52 and LCD 16x2. I build circuit and simulation in Proteus. It works normally. But when I build PCB, LCD can't display the value. I just adjusted rheostat to change LCD's contrast and it worked.Can you told me the mistake that I have?...Read more

character lcd - QC1602a Font Color

I have an unbranded QC1602A V2.0 display connected to a Raspberry Pi over 4-pin interface mode. Backlight and contrast are set in hardware, neither are controlled over the Raspberry Pi.If I setup the display as it should be (16x2 characters of 5x8 pixels each), the text is displayed in a very hard-to-read dark color:But if I set the display to 16x1 characters, 5x8 pixels each, the font suddenly switches to a very clearly readable white font:The code I used for testing was this:from RPLCD.gpio import CharLCDlcd = CharLCD(rows=2,cols=16, pin_rs=1...Read more

character lcd - Wiring up a 1602L/1602S LCD and switches

I need to replace a 1602L LCD (winstar i think) with an ACM1602S LCD.The original lcd had this resistance RAalso the end of the white wire from the switch was connected to the part that is marked J16, but not I can remember which of the three points.I think the other connections are equivalent. Full gallery here.If anyone can help me, I would be gratefulDatasheet for the original lcd is here...Read more

Weird behaviour from a 40x4 LCD Character Display

We have a fire monitoring/management panel which has a 40x4 character display attached to provide information in the event of a fire.It has recently started "glitching out", it displays random characters/glyphs for split-seconds in random places on the display. These are valid alphanumeric characters (not just random pixels etc), which leads me to think the LCD controller is damaged, which happens to be on-board the display PCB.We have had a quote provided to replace the panel, but we'd much rather replace just the character display (huge diffe...Read more

psoc - Character/Numeric TN LCD too Dim with a Head on View as Apposed to a Side View

I am using an LCD-S2X1C50TR and direct driving it with a PSoC 4200 Microcontroller. I was testing my circuit by viewing the LCD at an angle and it looked fine. Until I put my eyes directly above it, do I notice that the contrast is terrible and difficult to read.Things I Noticed: Bringing up the supply voltage from 3V to ~4V obviously made it better, but I was curious on why it's behaving this way. The device is rated 3V~5V on DigiKey, yet at 3V, it's only visible with a side view. Edit: I suppose DigiKey just screwed me over. Upon looking at i...Read more