iamlark Posted September 2, 2005 Report Share Posted September 2, 2005 so i'm having lcd problems. mios studio says that my core is good (hooray!). 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. any ideas on what could be going wrong? Quote Link to comment Share on other sites More sharing options...
pwx Posted September 2, 2005 Report Share Posted September 2, 2005 hi!as long as there´s no mios in the pic, the black rows in the display should be normal.... :)pwx Quote Link to comment Share on other sites More sharing options...
Jidis Posted September 2, 2005 Report Share Posted September 2, 2005 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. ;)Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Â Good luck!George Quote Link to comment Share on other sites More sharing options...
iamlark Posted September 3, 2005 Author Report Share Posted September 3, 2005 If that's the 1022 datasheet I just looked at, I think their janitor may have drawn that up. ;)yeah, no joke.right now, i am clueless and i am begging for help. (i probably should get a better LCD, but i can't afford it right now)here are the schematics for the lcd1022:http://www.bgmicro.com/pdf/2x16el.pdfi 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. ho-hum.... Quote Link to comment Share on other sites More sharing options...
raphael Posted September 3, 2005 Report Share Posted September 3, 2005 from the data sheet, it says that it uses db4-db7 for 4-bit operation. Why you want to use it in 4Bit mode ???This is a standard LCD with HD44780 controller. So just connect D0-D4 with the core and it should work.Raphael Quote Link to comment Share on other sites More sharing options...
iamlark Posted September 4, 2005 Author Report Share Posted September 4, 2005 Why you want to use it in 4Bit mode ???This is a standard LCD with HD44780 controller. So just connect D0-D4 with the core and it should work.Raphaelthe 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 :'( Quote Link to comment Share on other sites More sharing options...
raphael Posted September 6, 2005 Report Share Posted September 6, 2005 Have you loaded MIOS?Without MIOS a black row is normal. With MIOS you should see READY in the 1. row.Raphael Quote Link to comment Share on other sites More sharing options...
iamlark Posted September 6, 2005 Author Report Share Posted September 6, 2005 yeah, MIOS seems to be loaded correctly. i was able to run the MBSID_interconnect_test and it checked out, so i can only assume that MIOS loaded correctly. it's ok though, it was a crappy LCD to begin with and it crapped out on me. i saw one on allelectronics.com that i liked. seems like it runs in 8-bit, so no need to edit the program (which i can't figure out how to do anyway). Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.