next topic »

[on:]

Morning,

I'm starting my first major project, to build a PID controller for temperature and humidity. That parts going ok, but i'm confused about which display to pick, so many choices, so many different controllers.

I'm within the UK and my preferable supplier is RS. I'm ideally after a 20x4 monochrome LCD. If possible controlled by serial connection, i'm using a mega so its no problem is its not.
Unfortunately they don't seem to sell any HD44780 controlled displays.

This is the closest I've manage to find:
http://uk.rs-online.com/web/p/lcd-monochrome-displays/5326818/

It's controlled by a ST7066U. Pin outs on page 9 of the datasheet:
http://docs-europe.electrocomponents.com/webdocs/06dd/0900766b806dda1c.pdf

Other controllers available:
NJU6450
NT7603H
PCF 2119RU/2/F2 COG
RW1067
S1D13700
SED1520
SPLC780D
ST 7565R
ST7036
ST7065
ST7066U
ST7565P
ST7565R-G
T6963C
UC1610

Can i get recommendations on whats compatible and has good library support?

[Reply #1 on:]

According to some notes that I have made for myself over the years the ST7066U controller is compatible with the HD44780U.

In general, if the row of connecting pins on the pc board is at the upper left then the pinout will be standard as well.   The boards with the row of pins at the lower left seem to be the ones with non-standard pinouts.

Be aware that there are no standards for the various serial to parallel 'backpacks' that are available.  Some of them have their own microcontroller and then you must hope that the person who programmed it followed all the rules and provided the instructions that you need.  They are simple to use if they do what you require.  Others don't consist of much more than an interface chip.  They are harder to use but at least you can be pretty sure that you will be able to implement all of the features of the LCD controller.  The available libraries seem to be improving on an almost daily basis.

Don

[Reply #2 on:]

Thank you Floresta.

I think it may be best for me to start out with a parallel connection then experiment with a serial one in the future, or perhaps a graphical display if i'm feeling fancy.

Right, time to order things and get working on a menu. Already had a play with my rotary encoder =D

[Reply #3 on:]

I'm within the UK and my preferable supplier is RS. I'm ideally after a 20x4 monochrome LCD. If possible controlled by serial connection, i'm using a mega so its no problem is its not.
Unfortunately they don't seem to sell any HD44780 controlled displays.

Well if you do get a LCD display that has a built in TTL serial interface (easy to use on a mega with it's 4 hardware serial ports thus saving lots of I/O pins) then you really don't need to be concerned about what LCD chip controller it uses to drive the lcd display. But rather you need to know all the serial control characters used to manipulate the display. Here is an example product that has links to all the serial commands that control this specific display.

 https://www.sparkfun.com/products/9568

Lefty