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I have looked over CtCs post regarding similar issues with his LCD, but still can get mine to budge. I was hoping to get some guidance on my issue. The issue being I can't get the LCD to work or interface with my PICAXE. Like Ctc, I am using the serial backpack from SparkFun. Here is my code:

pause 1000
setfreq m8

pause 2000                        
serout 1,T9600_8,(124, 4) 'Sets 20 char (3)    |
pause 200                        
serout 1,T9600_8,(124, 6) 'Sets 4 line (5)    |

pause 1000
serout 1,T9600_8,(0x7c, 128)    'Sets backlight full on (128-157 '128 is full on

pause 1000
serout 1,T9600_8,(254, $01) 'Clear Screen


    pause 200
    serout 1,T9600_8,(254, 128)    'Sets line 1 position 1
    pause 200
    serout 1,T9600_8,("line 1")
    pause 200
    serout 1,T9600_8,(254, 192)    'Sets line 2 position 1
    pause 200
    serout 1,T9600_8,("line 2")

goto main


If I turn the 10k trim pot on the back to adjust the contrast, for a moment I see "blocks", but not text. Any clues?

photo.jpg142.85 KB

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Take a look at the command I posted for the backlight control.  If you look at the datasheet for the SparkFun LCD Backpack, 128 will turn off the backlight so you won't see any text on the screen although it will be there.  157 is full on.  Try that and see what you get

Looking at your code above here is what I gather:


1. You have sent commands to set the controller up as a 16 character by 2 line display:

   serout 1,T9600_8,(124, 4)

   serout 1,T9600_8,(124, 6)


2.  You actually turned the backlight off in the following command:

   serout 1,T9600_8,(0x7c, 128)

It should be serout 1,T9600_8,(0x7c, 157) or serout 1,T9600_8,(124, 157) to set backlight at 100%


3. To clear the display try this:

   serout 1,T9600_8,(254, 1) 'Clear Screen

Tell us what your setup is?

A. What processor?

B. What firmware version?

Have you got the serial in from the LCD connected to physical pin1 (bad) or output 1 (good according to your code) of your processor?

I am using a 14M, but have access to all of them if I need to swap it out for whatever reason.

Firmware is 9.C

The LCD RX line is connected to output1, not pin 1.

Humor me then and try a 28X1 which is what CTC was using. Just in case it's a 14M problem.
Same thing with the 28x1

Yeah, I was heading in that direction.

Gimme a few minutes. I'll reply back with my findings.

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Like firmware?

Which Picaxe?

printing just plain ascii 65 through 65 + 26 (A-Z)?

I am not the coding whiz on the picaxe, so let someone else give you the obvious checks on that one....