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???
07/11/10 06:16
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#177230 - LCD display delay problem?
Responding to: ???'s previous message
Is it possible that the LCD code delay is greater than the data transfer time, ( and maybe therefore, the gibberish on the LCD screen)?

Here are some observations I made earlier...
This is the code I'm using to display data on the LCD.
void lcddata(unsigned char value)
{
ready();
rs=1;
rw=0;
en=1;
lcd_port=value;
en=0;
return;
}
void ready()
{
busy=1;
rs=0;
rw=1;
while(busy==1)
{en=0;
en=1;
}
return;
}

 

Here's a bit of math I did to determine the delay I have between two consecutive data acquisitions...
4800 bits in one second
8 bits in 1.67 milliSec.

Thus i have around 1.6 ms before the next byte comes into the SBUF. Therefore the delay of the above code must be <=1.6ms.
But when I used the Keil debugger to find out the delay of the above functions...I found it to be 8.4 microseconds(but I don't know whether I did it right.)So according to my calculations, the lcddata() function isn't a culprit.


List of 41 messages in thread
TopicAuthorDate
Problems with GPS Receiver and the 8051            01/01/70 00:00      
   Take a step back.            01/01/70 00:00      
      Always very baudrate by measuring it            01/01/70 00:00      
      Roger that..            01/01/70 00:00      
         Noise ?            01/01/70 00:00      
         RE: Random data            01/01/70 00:00      
            Working on the hyperterminal...            01/01/70 00:00      
               Tx Rx pins            01/01/70 00:00      
                  The connections seem to be fine...            01/01/70 00:00      
                     GPS emulator            01/01/70 00:00      
                        Keil Simulator            01/01/70 00:00      
                           Great idea...            01/01/70 00:00      
                              Simulating GPS seems to work...            01/01/70 00:00      
                                 scope time            01/01/70 00:00      
                     LCD display delay problem?            01/01/70 00:00      
   Sio_poll_0.6.zip            01/01/70 00:00      
      comp.xx not nicest            01/01/70 00:00      
         Thanks Per.            01/01/70 00:00      
            Ask for suggestions how to improve the code            01/01/70 00:00      
               Good advice...            01/01/70 00:00      
      Hyperterminal works            01/01/70 00:00      
         A doubt in the datasheet...            01/01/70 00:00      
            it means that they do not know            01/01/70 00:00      
            Correct            01/01/70 00:00      
            why            01/01/70 00:00      
   Let's Do a Sanity Check            01/01/70 00:00      
      EM406            01/01/70 00:00      
      It is very weird, but...            01/01/70 00:00      
         Then is is time for....            01/01/70 00:00      
            Oscilloscpe.            01/01/70 00:00      
               Verify voltages with scope            01/01/70 00:00      
         re inversion (not) needed)            01/01/70 00:00      
      Use the simulator!            01/01/70 00:00      
         Don't really know...            01/01/70 00:00      
            Using the Keil Debugger/Simulator            01/01/70 00:00      
               Working! Now...            01/01/70 00:00      
                  Expensive solution            01/01/70 00:00      
                     True...            01/01/70 00:00      
                        SD_Card_and_DCFS16.zip            01/01/70 00:00      
                           broken link            01/01/70 00:00      
                     not all "level-converter chips" are special            01/01/70 00:00      

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