pic16f690 serial communication c code beautifier

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I am trying to interface a pic16f690 with a LCD (Hitachi 44780).

I have been searching the whole internet but didnt find any results.

I used this tutorial ( ) as a basic start and used his code(see below).

I have connected RS to RC7, RW to RC6 and E to RC5 and port D4 tot D7 to PORTB of the pic for 4 bit communication.

When i turn down the pot the black boxes only get less visible.

I checked all the connection a hundred times, so that wont be the problem also.

This should be inside main(): unsigned char counter0;Overflow counter int count0; char output Hello; char output2 World.

Maybe it is something with my delay I am using the standard delay from the pic.h header.

MPLAB X keeps saying that he is unable to resolve identifier delayms.

I already tried building my own delay but that didnt work either.

If it compiles despite the warning then you can very safely ignore it.

While there are several areas for improvement nothing jumps out as bad in the code.

Once it works you can run thru and pull out some of the incredibly long delays (you should be able to print more then 2 characterssec).

Do you have a schematic to check Did you put in that contrast pot.

And i added a 10k pot between VCC and VO, and that gives blackboxes when on 10K and nothing when he has a value of 0.

I even tried to short VO to ground, which also gave me black boxes.

Also the backlight is connected with a 100ohm resistor to VCC, but on my LCD the VCC and ground are switched in comparison with the schematic in the tutorial.

This is my new code, I hope you can help me one more time Thanks.

Is the 100ms delay important If it is, then its possible your code does not provide enough delay because 100 may be too large for the delayms() (as the MPLABX warning states).

It this compiles then the compiler can find that identifier (the function name).

Reading the help file (otherwise known as the MPLAB XC8 C Compiler Users Guide) shows no max number for any of the delay macros.

HOWEVER. it does state the following.

This symbol should equate to the oscillator frequency (in hertz) used by the system.

Try that and see.

I would hope the XC8 library would throw an error without this importaint symbol being defined.

Pic16F690 Serial Communication C Code Beautifier