20x4 Batron LCD

[matt1eg]

Hi

I have got my self a nice little 20x4 lcd from batron, **broken link removed**, but I can't get it to work properly. I have got it all connected up and it turns on fine with backlight I am using this driver and I can get it display text but it seems to be overwriting itself on certain lines.
i.e when using the test program and standard 20x4 line addresses i should see:

1st line 'this is the 1st line'
2nd line 'this is the 2nd line' etc

but i get:

1st line 'This is the 1st line'
2nd line '1st lineThis is the'
3rd line 'Next is the 2nd line'
4th line '2nd lineFinally the'

I tried changing the addresses to

1st line 0x00
2nd line 0xc
3rd line 0x40
4th line 0x4c

this gave:

1st line 'This is the Next is'
2nd line 'Next is the 2nd line'
3rd line 'This is the Finally'
4th line 'Finally the 4th line'

Using the addresses for the HD66712U chip which i thought this LCD uses i get a complete mess:

1st line 'the 4th line1st line'
2nd line '1st line'
3rd line 'This is the 3rd line'
4th line '3rd line'


It seems to print the first 12 characters fine using first 2 sets of addresses but the last 8 seem to get copied to and from other lines, I just can't work out whats going on.

has anyone used this display before or have any ideas as to why it is doing this?

Any help would be great

 

[ericgibbs]

hi,
Have you tried 0x80,0xD0,0x90,0xD0..... 1,2,3,4

EDIT:
the other set I have on file is:

0x80,0xC0,0x94,0xD4....1,2,3,4

 

[matt1eg]

Hi, just tried it and get:

1st line 'This is the 1st this'
2nd line '1st this is the 3rd'
3rd line ' Fina'
4th line ' finally the 4th'

Thanks anyway though.

How come the first line starts at the same place even though it usuing 0x80 instead of 0x00?

 

[ericgibbs]

Hi, just tried it and get:

1st line 'This is the 1st this'
2nd line '1st this is the 3rd'
3rd line ' Fina'
4th line ' finally the 4th'

Thanks anyway though.

How come the first line starts at the same place even though it usuing 0x80 instead of 0x00?

Because D7, bit is redundant on some lcds.

What I suggest you do now is, No its not panic.!

Write a very long string of characters to the lcd, starting at address 00.

If you use a string of known structure you will find the line starts.

eg:01234567890ABCDE.......XYZabcdefghijklm......xyz etc

Do you follow.?

 

[matt1eg]

Panic has already set in, using an LCD was meant to be the easy part of the project!!

I think I got what you meant, I have used

"\fabcdefghijklmnopqrstuvwxyz01234567891011121314ABCDEFGHIJKLMNOPQRSTUVWXYZ"

and i get:

1st line 'abcdefghijklmnopqrst'
2nd line 'mnopqrstuvwxyz012345'
3rd line '121314ABCDEFGHIJKLMN'
4th line 'GHIJKLMNOPQRSTUVWXYZ'

 

[ericgibbs]

Panic has already set in, using an LCD was meant to be the easy part of the project!!

I think I got what you meant, I have used

"\fabcdefghijklmnopqrstuvwxyz01234567891011121314ABCDEFGHIJKLMNOPQRSTUVWXYZ"

and i get:

1st line 'abcdefghijklmnopqrst'
2nd line 'mnopqrstuvwxyz012345'
3rd line '121314ABCDEFGHIJKLMN'
4th line 'GHIJKLMNOPQRSTUVWXYZ'

Ive taken a copy, Ill see if it makes any sense, looks a weird puppy.

 

[ericgibbs]

hi,

I make it this: if not I dont know at this time.
00,28,40,48

 

[matt1eg]

Put those addresses in and I get

1st line 'This is the 1st line'
2nd line '1st line'
3rd line 'This is Finally the'
4th line 'lly the 4th line'

It's very strange. Could it have something to do with an extension driver? The datashhet isnt very clear on its setup.

 

[matt1eg]

Have sorted it The datasheet for the controller says that for 4 line LCDs it uses an extension which can only be written to when the bit is enabled (page 407). Found this at AVR Freaks :: View topic - LCD with KS0073 controller.
Found this link looking for information about extension drivers.



Thanks very much for your help

 

[Alpix]

Hi,

I am having exactly the same problem here using Batron display BATRON|BTHQ42003AV-STF-06-LED WC|LCD MODULE, ALPHANUMERIC, 20X4 | Farnell United Kingdom
Page 407 refers to raising Bit Register Enable (RE). I have tried raising Bit Enable (E) pin 6 of the display and this has shirted the characters but not in an expected way.
Is this the correct bit or am I missing something here?

Thanks for any help...