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???
02/02/08 09:11
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 		 #150205 - HD44780 in 4 bit mode timings
Responding to: ???'s previous message
I am impressed that you are following the data sheet. Your code looks OK apart from the PORT |= data error.

When you get it all working, you will either read the Busy flag or rely on instruction timing between commands.

The enable strobe only needs to be >500nS.
Regular writes only need to be >37uS (some chips ask for 42uS).
Only RTN and CLS commands need >1520uS (some chips ask for 164uS).

Visit AvrFreaks.net to see an average three different threads every day about why LCD initialisation does not work. They ALL violate the timing sequences.

David.

List of 44 messages in thread
TopicAuthorDate
LCD in 4Bit mode trouble            01/01/70 00:00      
   For a start            01/01/70 00:00      
   How to post source code            01/01/70 00:00      
   HD44780 in 4 bit mode timings            01/01/70 00:00      
      Thanks, but still doesnt work            01/01/70 00:00      
         Tied lines            01/01/70 00:00      
            RW line tied to GND            01/01/70 00:00      
               R/W is tied to ground by hardware            01/01/70 00:00      
               have a look at this in code library            01/01/70 00:00      
            It worked!            01/01/70 00:00      
               It worked!            01/01/70 00:00      
                  d0-d3            01/01/70 00:00      
                     d0-d3 I still insist they should be left open !            01/01/70 00:00      
                        Proof            01/01/70 00:00      
                           They already have internal pullups            01/01/70 00:00      
                              Where ?            01/01/70 00:00      
                                 Please find the " Pull-up MOS " in the datasheet            01/01/70 00:00      
                                    Thanks            01/01/70 00:00      
                        I never insisted ont tieing them            01/01/70 00:00      
   can\'t help it            01/01/70 00:00      
      Noritake            01/01/70 00:00      
         Noritake            01/01/70 00:00      
            'life' for as long as it lasts            01/01/70 00:00      
               Please provide the datasheet part info            01/01/70 00:00      
                  I do not have it            01/01/70 00:00      
   I never insisted ont tieing them            01/01/70 00:00      
      Powertip - pc1602f            01/01/70 00:00      
   2 more things            01/01/70 00:00      
   I am getting 50\'000Hrs , with 80Cd/m2 , they            01/01/70 00:00      
   I work in 4 bit mode            01/01/70 00:00      
      All that code reduces to:            01/01/70 00:00      
         Thanks by the code size reduction            01/01/70 00:00      
            Tools            01/01/70 00:00      
               sure, but why            01/01/70 00:00      
                  time for a new thread...            01/01/70 00:00      
            Free IDE            01/01/70 00:00      
               it does not make sense            01/01/70 00:00      
                  Ops,,, Topic changes!            01/01/70 00:00      
                     one thing at a time            01/01/70 00:00      
                        Why bin file and not hex directly            01/01/70 00:00      
                  re: it does not make sense            01/01/70 00:00      
                     it does not matter 'how long'            01/01/70 00:00      
                        Not recommending anything            01/01/70 00:00      
         The swap command should not exist !!?            01/01/70 00:00      

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