LCD module test or how to connect the beast to PC printer port.
I received few requests how to test the LCD module using easy to obtain software. Maybe people are to lazy to search internet… So, here is simplified instructions how to connect standard LCD module to PC computer port (LPT) and how to configure WinAmp plugin.
The circuit diagram is very simple. Attention! Some old or nonstandard, “winter”, modules require additional power supply to be connected to Vee pin (contrast). But most of the modules are working from regular voltage, and you connect Vee pin to ground or using some trimmer connect it between Vcc (+5V) and ground (GND). All standard modules after power-up show one dar line to demonstrate that they are working.
The circuit itself is very simple. Take note to trimmer on Vee.
This is old SHARP LCD module based on HD44780A00 chip.
This module is younger. It is ROHM made with SEC 701 / KS0070B chip.
This is big LCD module. It is Sanyo made LCM-544E. 4 x 40 symbol module with double controller. The connector is a bit different from standard one. It is possible to pin-point the pinout checking it against controller chip. If you are too lazy to do this job, you may use this table (please leave link to my pages if you post this data in your pages):
Connection diagram of LCM-544E, standard LCD and printer port:
Standard 14 or 16* pin |
LPT pin |
LCD Pin Name |
LCM-544E |
1 |
18-25 |
GND |
15, 16 |
2 |
– |
Vcc |
14 |
3 |
– |
Vee (-5…+15V)** |
13 (~-2V) |
4 |
16 |
RS |
11 |
5 |
14 |
R/W |
12 |
6 |
1 |
E0 |
9*** |
7 |
2 |
D0 |
7 |
8 |
3 |
D1 |
8 |
9 |
4 |
D2 |
5 |
10 |
5 |
D3 |
6 |
11 |
6 |
D4 |
3 |
12 |
7 |
D5 |
4 |
13 |
8 |
D6 |
1 |
14 |
9 |
D7 |
2 |
|
17 |
E1 |
10*** |
15 |
|
BACKL+ |
|
16 |
|
BACKL- |
|
*-sometime pin 15 and 16 are placed near first pin.
** – contrast: for standard module 0-5V, sometimes need to supply negative voltage, sometimes more than Vcc (up to +30V!).
***- two controllers on same board. Selectable by E pin.
Now few workd about WinAmp configuration. Please download Winamp LCD plugin from internet. If you are using WinXP OS, please download low level printer port drivers: port95nt.exe
Now configure you winamp plugin like this:
Don’t care to line called Win9x, it is still working on XP…
Here is the details of the configuration. This image is showing big, 4 x 40, module configuration.
HI, i have an lcd based on hd44780a00 too and having trouble initializing with atmel 89c51. in simulation(proteus) it is working just fine. but here it is not. Please help me out. give me some code or like that so that i can understand. i can understand assemble and c so no language problem
All source code is published in this web pages. Also, I am using free available software by Peter Fleury (http://jump.to/fleury) for LCD interface.