LCD 4X40 Futurlec

[DaveC3]

Here is some code I used to control the 4x40 display. This is just the LCD part that demonstrates the enable selection

'**** LCD *******************************************************
'Set LCD Data port
DEFINE LCD_DREG PORTB
'Set starting Data bit (0 or 4) if 4-bit bus
DEFINE LCD_DBIT 4
'Set LCD Register Select port
DEFINE LCD_RSREG PORTB
'Set LCD Register Select bit
DEFINE LCD_RSBIT 0
'Set LCD Enable port
DEFINE LCD_EREG PORTB
'Set LCD Enable bit
DEFINE LCD_EBIT 3
'LCD RW Register PORT
'DEFINE LCD_RWREG PORTB
'LCD read/write pin bit
'DEFINE LCD_RWBIT 5
'Set LCD bus size (4 or 8 bits)
DEFINE LCD_BITS 4
'Set number of lines on LCD
DEFINE LCD_LINES 4
'Set command delay time in us
DEFINE LCD_COMMANDUS 2000
'Set data delay time in us
DEFINE LCD_DATAUS 50

LCD1_Disable    var portb.2
LCD2_Disable    var portb.1
'*** Program variables *****************************************



lcdcnt     var  byte
lcdlen     var  byte
lcdline var byte
lcd var byte
lcdfunction var byte


'***************************************************************

' Initialize LCD
input LCD1_Disable 
input LCD2_Disable 
LCDOut $fe,1   'clear lcd
pause 100
LCDOut $fe,2   'home
LCDOut $fe,$0c 'Curser off
LCDOut "              USB 4X40 LCD   "
LCDOut $FE,$C0
LCDOut "              DAVE CUTLIFF    "
low LCD1_Disable 
input LCD2_Disable 
LCDOut $fe,1   'clear lcd
LCDOut $fe,2   'home
LCDOut $fe,$0c 'Curser off
LCDOut "         Highspeed USB Project  "
LCDOut $FE,$C0
LCDOut "             August 2005    "   
pause 100
goto idleloop

[Bill Legge]

1. Joe S. I have not been able to get my 4X40 LCD to work - so I'm hardly the fellow to give you advice. However, I think you are right and the 4X40 is built like two 2X40 displays that have separate ENABLE pins and the rest are common. I presume one simply swaps from ENABLE1 to ENABLE2 according to what needs to be displayed.

2. The new pin-out from Futurlec is NOT the correct one (Futurlec sheet is for a device 4004 and mine is a JHD404A1 with a different number of pins.) Adjusting/guessing the connections has yielded only fleeting black blobs - and yes, I do know that black boxes may be caused by too high contrast setting.

3. I'm a bit irritated that Futurlec is selling a $40 odd LCD device and can't publish the correct spec sheet - and it's not to be found on the internet. There are quite a few different pin-outs for other 4X40 LCDs but none seem to work on the JHD404A1.

4. Anyone go it to work? Futurlec must have sold a fair number of thes LCDs

Regards Bill Legge

[rhino]

Bill - If it does happen to have 2 controllers, here is an excellent way to control it.
http://www.picbasic.co.uk/forum/showthread.php?t=626

Hope it helps.

[Bill Legge]

Rhino,

Thanks for the info. I have got a different 4X40 (DisplayTech LTd closing down sale for $5, how's that for a bargain) and - IT ALL WORKS OK - along with the code/circuits for driving two ENABLE pins.

I would still like to track down the pin-out for the Futurlec JHD404A1 if anyone out there has the info.

Regards Bill Legge

[RussMartin]

I use a lot of Crystalfontz displays with good (great!) success.

http://www.crystalfontz.com/

[rixter]

Hello,

I managed to get the Futurlec 4 x 40 LCD working. In my case, I did this with a BASIC Stamp. I hope I'm not escorted to the door from this forum. I found this forum to find a solution for communicating with an LCD. See attached photo.

Bill's initial thread actually had the correct pin assignments that were the key to getting me started, although the Futurlec LCD has no pins 17 & 18. Internet research had consistent documentation on 4 x 40 LCD with two rows of pins having different assignments than those posted on Futurlec's site. Those are clearly WRONG! Also, A and K connections are for the back light and are straightforward.

The second challenge was understanding how to address the 3rd and 4th lines on the display. My experience with LCD displays was limited to 2 x 16 and 4 x 20 serial units that have an entirely different way to address the screen coordinates. The 3rd and 4th lines are addressed with the second enable pin. This forum clued me in on that .. thank you. So I had to initialize both controllers in the LCD and communicate with the device as basically a stack of two 2 x 40 LCDs in one unit. The LCDCMD command in PBASIC allows me to address a set of pins in 4 bit mode while allowing some flexibility on which pin is the enable pin. This permitted me to address both sets of lines by adding the one additional connection to the LCD for the extra enable connection.

I am not versed on PIC language, but I'm sure it's doable if I've done it with the BASIC Stamp.... code attached.

Rick

[Bill Legge]

Rixter,

Thanks for your message and I'm pleased to learn that the pin-outs in the first post are correct. I must have made some wiring error because they would not work for me? I will have another go.

I have, since then, got some different 4X40 LCDs, with correct tech details, and they work well using the method posted by RHINO - a couple of resistors on the two ENABLE pins and a bit of code.

One mistake that took me a long time to find was using the PBP command "CLEAR" after the definition on the LCD1-Enable and LCD2-Enable pins - the CLEAR command clears the definition:

This won't work:
LCD1-Enable VAR PORTD.1
LCD2-Enable VAR PORTD.2
CLEAR

This will work:
CLEAR
LCD1-Enable VAR PORTD.1
LCD2-Enable VAR PORTD.2

Good luck - get off the Basic Stamps and into PICs soonest!

Regards Bill Legge