when i connected my lcd, all on got on the screen was a row (top) of black boxes for a second, then nothing.
i’m using the 20x2 lcd1022 from bgmicro and checking the datasheet, i believe that i have everything wired correctly.
from the data sheet, it says that it uses db4-db7 for 4-bit operation.
i’m not quite sure how the lcd debug in mios studio works, but i sent a message to it, and once again got the row of black characters that disappeared after a second.
I don’t think they should go away after a second though. (?) I use the debug in MS for the ability to send text to the display for layout purposes, but I guess you’d need a functioning connection first.
I’m only familiar with the two displays I’ve used here (16x2 & 40x2, both with 44780 chips and 14 connections + 2 for light). I think a 4 bit connection requires a little more work than that. Maybe someone more knowledgeable here can help out. It looks like there are some software edits involved (search the forum for “4 bit LCD”).
If that’s the 1022 datasheet I just looked at, I think their janitor may have drawn that up.
                                     Good luck!
i have connected everything as it says on the bottom page 4 with the exception of B+,B- (this lcd needs EL inverter, which i haven’t build yet)(would this matter???). so, B+,B- and DB0-4 are hanging free.
This is a standard LCD with HD44780 controller. So just connect D0-D4 with the core and it should work.
Raphael
the data sheet said it’s 4-bit and to use db4-7. i’ll give 0-3 a try. thanks!!
update: 0-3 gave me nothing. for a while, i was still getting the row of characters (when hooked to 4-7), but then the stupid thing crapped out on me. i’m about to throw this whole project through the window with the amount of problems i’ve had
