lcd panel 1x16 character manufacturer

Custom and standard monochrome character and graphic LCDs from Orient Display are available in a wide variety of backlight color combinations. These devices feature a low power LED backlight, high brightness per watt, wide operating temperatures, positive and negative image options, as well as industry standard sizes and interfaces. Orient Display utilizes the common HD44780 parallel interface chipset for easy connectivity.

Liquid crystal displays (LCD) come in two main types that are of interest to hobby and DIY makers; Character LCD displays and pixel / graphic LCD displays. This intro “How To” will be covering the more popular and less expensive character LCD displays based on the very common Hitachi HD44780 controller.

LCD displays come in many sizes most often named by the number of rows and then the length of the display line. For example a 1x16 LCD display will have one row of sixteen characters and a 4x20 LCD display will have four rows with twenty characters in each.

LCDs can be have backlighting or be reflective (think calculator). In either case the programming that goes into working these displays is the same. LCDs with backlight normally use two pins to provide power to the backlighting.

2x16 character LCD with backlighting. Note, screen is all black, but to display characters the crystals move to allow the backlighting to show through.

Most LCDs that are being made now come with one row of sixteen pins. The first fourteen pins are used to control the display and the last two are for the backlighting (if the display has backlighting).

Older LCDs sometimes came with two rows of seven making a fourteen pin connector. These fourteen pins, most often, have the same signals on them that the 1x16 pin displays do. For example, pin #1 on the 2x7 connector is the same signal as pin #1 on the 1x16 connector, they are just arranged differently. If you have a 2x7 pin display but need to connect it to a 1x14 (1x16) backpack or device, the basic

LCDs based on the Hitachi HD44780 controller must be initialized after they are powered-up. The reason that the LCDs must be initialized is because there are a few critical options that the display must “know” before it can work or communicated properly.

The most import of which is wether to use an eight or four bit data interface. Hitachi and compatible LCDs can be set to use either 8 or 4 of the data pins to communicate with the host controller that is driving it. Using a four pin data bus lets you save on pins, but your controller must divide each instruction into two four bit segments and then send them one at a time to the display. So the trade off is less pins versus more programming and slower communication. (The reduced speed of having to send data twice has little effect on the display, but it does busy your processor for a longer amount of time.)

Ok, so you initialized your new 1x16 display and cleared it so that the cursor is at the first character position. Now you start sending your “Hello World” message to the screen.

When you send the LCD a character to display, you are not actually sending it to the screen part of the display, but rather a memory location that the display uses to know what to display on the screen. The problem here is that the memory location and the mapping to positions on the screen are not always sequential.

The “Hello World” example above is often what gives people trouble using a 1x16 LCD for the first time. Here the “r” “l” “d” went into memory address 0x88,0x89 and 0x8A which are not visible on this display !

Note that from the eight to the ninth character position the memory jumps. So, to finish displaying “Hello World” the controller would have to jump to memory location 0xC0 (at the red arrow) to continue displaying “rld”.

Solution: When you are ready to display a character in the ninth position on a 1x16 display you simply send the memory address to the display, but as a command.

For 1x16 and all the display larger then this, the memory mapping of the DDRAM (Display RAM) is not in the same range as the other commands, such as “clear display”, “home display” etc... so there is no problem sending the memory address as a command.

When it is actually time to use an LCD you have a few choices of how to do it. You can connect it directly to your Arduino or micro-controller (MCU) and use a lot of pins and wires or your could use a backpack.

Using a backpack has a few advantages over connecting the LCD directly to your micro-processor. Besides using less wires, (and pins) some backpacks take over the entire job of driving the display. All your code has to do is send the text out of the appropriate interface, I2C, serial, SPI etc ... This can save your micro-controller a lot of memory, and processor time. And, it also lets you get your projects working sooner, since you do not have to code and debug software to drive the display on top of the rest of your project.

B. Backpacks that reduce the pin-out burden on your MCU. With this type of backpack, your MCU still initializes and drives the LCD, but through an interface with fewer wires.

Most displays work with the standard 128 ASCII characters. Often times, the displays are also able to display other characters, these include Asian characters and other special symbols and icons.

Your micro-controller measures a sensor and returns the value of five. You send the value to the display and you either get nothing or a strange looking character.

The EA 9707-V24S interface allows dot-matrix LCDs to be programmed easily and quickly. The interface can be soldered directly onto almost all dot-matrix modules. It is connected to a standard RS-232C interface.

After looking at the BP LCD interface I got to thinking that driving the LCD directly with FT232R is a bad idea and that using the "595 simplifies the software immensely. And so it follows that it would be possible to build a backpack for a LCD to run off of the USB bus. Sort of like the Olimex PIC-MT-USB but without the PIC. Should be a lot cheaper.

The standard board size for a basic 16x2 character LCD display is 80x36 mm and has the 1x16 connector in the top left front. There are four mounting holes. There are a lot of variation in the sizes and connectors. Some even have the 1x16 connector at the bottom left but the pinout is 14-1,16,15 left to right. Some displays have the 2x8 connector but pins 1 and 2 have reversed voltage polarity. I think we should stay with what we have discussed and with a board size of 80x36.

Here we will list the LCDs we have tested with the LCD backpacks successfully and explain how to connect them if they can"t be plugged into the backpack directly. We encourage users to add LCDs they have tested successfully with the USB LCD backpacks to this list.

PIN6-9 DATA Orange LCD pin 6 to Ardu Pin 5, LCD7 to 4, 8 to 3 and the LCD Pin 9 to Ardu Pin2. (kind of cross wired, I have tried the other way around with identical result)

With this Setup I can set a cursor to any position, have it blinking, turn the display on/off, but I don´t get any characters displayed with the "print" or "write" commands.

This code kind of "grew" out of the basic "Hello World" sketch when I was adding different LCD related commands to see what the action is. Basic result: all commands in that sketch work except "print" and "write".

1)After I pull and re-connect the +5V to the LCD it weakly shows the 8 dark squares on the left side of the display, with a cursor blinking and scrolling slowly from left to right, blinking for 5 sec on each slot, then disappear for good. The squares remain dimmed until I re-load the code to the Arduino. Then the squares disappear and the blinking cursor has its full contrast again and it is doing its sketched blinking.

4) During the initial PIN identification phase, I had situations, where all kinds of different characters were displayed. That looked pretty promising and tells me that the character ROM worked then. I cannot recall, which PIN combinations caused these indications. At that time I had not figured out yet, that there is no R/W pin.