Email: Password: Remember Me | Create Account (Free)

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
07/28/05 16:37
Modified:
  07/28/05 16:43

Read: times


 
#98407 - Yes it works
Responding to: ???'s previous message
J Cena said:
I have just tried your new program but I am afraid I can't see a &*%$**& thing on line 2, Did it work on your end ?


Yes, I tested the above on my end and it did work this time.

As a final exercise, you might try:
  MOV R7,#40h
  MOV A,#'0'
SPACELOOP:
   LCALL WRITE
   INC A
   DJNZ R7,SPACELOOP


This will cause printable characters to be displayed wherever possible. Displaying a lot of spaces probably wasn't a good idea because, for all we know, it is displaying them but you don't see them because they are spaces.

If you do get something printed on the second line from this final test, please tell us what characters you see on the second line.

What hardware faults I should look for? I am getting more convinced that it has to do something with hardware.


I'm no longer sure what's wrong after the above test didn't work, especially if you can see the darkishness that Steve described on the first line but can't see anything on the second line. That does suggest a problem in configuring the LCD for 1-line operation rather than 2-line operation; but since your code works here it seems your initialization sequence is ok. Which makes me wonder if something is causing the 38h initialization command to not make it to your LCD as 38h but somehow get changed to 30h (which would be 1-line mode and cause only your first line to exhibit that darkishness).

You could check continuity on each of the LCD lines on your board with the LCD removed and see if you have any shorts, particularly a short involving DB4 (which could impact 38h being received as a 30h). I'm not convinced that's the problem, though, because I would expect a short on DB4 to also be apparent when you write "HELLO" to the LCD.

Regards,
Craig Steiner


List of 37 messages in thread
TopicAuthorDate
89C2051 and LCD            01/01/70 00:00      
   Notes            01/01/70 00:00      
   8052 tutorial, ever used?            01/01/70 00:00      
      STOP!            01/01/70 00:00      
      Nope            01/01/70 00:00      
         and read the tutorial - see left column            01/01/70 00:00      
            which he clearly states he has done            01/01/70 00:00      
   Whats wrong with 2nd line?            01/01/70 00:00      
      Works here            01/01/70 00:00      
         re: works here            01/01/70 00:00      
            Try different cursor position            01/01/70 00:00      
               Different Cursor position            01/01/70 00:00      
                  Whats on screen            01/01/70 00:00      
                     re: darkish lines            01/01/70 00:00      
                     Contrast            01/01/70 00:00      
                        True,            01/01/70 00:00      
                           Maybe            01/01/70 00:00      
                              What about this?            01/01/70 00:00      
                                 Strange            01/01/70 00:00      
                  Ok then try this            01/01/70 00:00      
                     or maybe this            01/01/70 00:00      
                        re: or may be this            01/01/70 00:00      
                           c language ?            01/01/70 00:00      
                              I think            01/01/70 00:00      
                              LCD is fine            01/01/70 00:00      
                                 Try this            01/01/70 00:00      
                                    re: Try This            01/01/70 00:00      
                                       Yes it works            01/01/70 00:00      
                                       my flat forehead            01/01/70 00:00      
                                          I agree            01/01/70 00:00      
                                          Or...            01/01/70 00:00      
   today            01/01/70 00:00      
   PROBLEM SOLVED            01/01/70 00:00      
      it was discussed            01/01/70 00:00      
      Isn't that because...            01/01/70 00:00      
      Glad you got it working            01/01/70 00:00      
         Startup delay            01/01/70 00:00      

Back to Subject List