Using LCD with micro becomes more complex with configuring
more signal lines.
I therefore use minimum 4data lines + 2 control lines
only. En & R/S. RW line permanently tied low and as such
I dont read busy signal. All you have to do is make small
delay for writing each instruction.Here is the tip for
writing:
"Programming Tip: The LCD interprets and executes our command at the instant the EN line is brought low. If you never bring EN low, your instruction will never be executed. Additionally, when you bring EN low and the LCD executes your instruction, it requires a certain amount of time to execute the command. The time it requires to execute an instruction depends on the instruction and the speed of the crystal which is attached to the 44780's oscillator input."
I have 20 x 4 line LCD working fine. To send data
I first set En HI then write first nible then with delay
lower the En. Then send second nibble same way.Data is
latched on falling edge. As I got all these lines in same
P1 I use just Oring instrn after masking nibble to 0000b.