pic,lcd masters....oves here

[aviv6371]

hello ,

i m b building running message with pic and lcd 44780 do i have
to connect the rd/wr wire of lcd to ground or i it has to be connected to the pic as a contol pin. in other words if i want to run message on the lcd do i ought to read from the lcd.

thanx in advance

avi

 

[haytham]

Hi
You can connect it to ground. In ths case you should wait about 2 ms between successive commands. Of course reading from LCD will fast the execution but you will lose I/O pin and also you will need some careful coding

Thanks
Haytham

 

[aviv6371]

hi,

i have to wait whether the pin rd is connected or not for proper operation of the lcd.
i think i would connect it to rd because i m working with the picdem plus unit.
but i have onother question-why does the pic16f877a has 2 pins of vdd and 2 of vss ???? and do i have to connect them both to vdd (short them) ???

thanx in advance,

avi

 

[eng.midofidodido]

Salam,

For the stability of your design u have to connect both VDDs and VSSs to the power supply.

Regards.