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Crosswinds
03-27-2012, 06:49 PM
Hello Guys!


Ordered a parallel graphic LCD from sparkfun. It is 128x64, and uses the KS0108B, found the object from the obex, and tried it out.


I followed the documentation in the obex, and translated it to the schematics that came with the LCD. But i get this very flimsy output. Please see video-link:
http://www.youtube.com/watch?v=CJTES9cKAHM

I have double-checked everything, but there is some simple explanation to what im doing wrong.

you guys got any ideas?


//Daniel

HShanko
03-27-2012, 08:07 PM
What I saw appears to be updating the screen way too often. Put a delay in the loop to slow down the images for us human eye/brains.

Crosswinds
03-27-2012, 09:24 PM
What I saw appears to be updating the screen way too often. Put a delay in the loop to slow down the images for us human eye/brains.


Hello! Thanks for your input, it was a good idea, but did not work.

This is what i get with the delay in place:

https://www.youtube.com/watch?v=k12y2NrGXlE

Erik Friesen
03-27-2012, 10:43 PM
Some ks0108 clones need slower updates, as the object doesn't read the ready state from the lcd. Try setting the delay in the assembly driver.

Erik Friesen
03-27-2012, 10:45 PM
try tdelay of about 300 or so, then pull it down until it fritzes, then give a margin of safety.

' Pin configuration

chs1 long |<CS1
chs2 long |<CS2
din long |<DI
rwr long |<RW
enable long |<Ena
reset long |<rst
outs long IOpins
datapins long DB0_DB7 'set to byte
db0 long DB0pin
'program
tdelay long 90 'this sets delay for lcd
allbits long $FFFF_FFFF
bit0 long |<0
bit1 long |<1
bit2 long |<2
bit3 long |<3
bit4 long |<4
bit5 long |<5
bit6 long |<6
bit7 long |<7
zero long 0
leftbits long %00000000_00001111 'masks for character placement
rightbits long %11110000_00000000 'in half slots
evenbits long %11111111_11110000
oddbits long %00001111_11111111
smallbits long %00000000_00011111

Crosswinds
03-27-2012, 11:39 PM
Hi guys!

And thank you very much for your input Erik.


I have found the problem, and i feel real stupid.

I did change the DI & R/W pins from 30 & 31 to 12&13. But forgot to make them outputs.
I feel so stupid because i did only concentrate on my wiring, i think i went through it 10 times, the datasheet did not match the pins in the file. But now everything works great, even without any delays!





and thank you Erik for the driver, just golden work :)


Best regards
Daniel