my lcd nit doesnt happends some of my devices

[TARHAN SAMAH]

hello ,

i want to have your advice in general:

We use lcd 16x2 for our master device and 20x4( lcd needs 5 v power) for the end devices, in both we use keyad to make a PİN OUT RESET OF THE STM CHİP ,

But for some device the lcd init happens very good for half of devices the lcd init half of time doesnt happen, all functions reset very well and its good working but lcd couldnt init and of course it not well seen .

We changed lcd delays , we changed lcd we changed chip it deosnt affect , i dont think its about our lcd driver because in half of devices it initialize very good !!!

Please can you have a look to my shcema whats wrong with that ? Thanks 

[Tesla DeLorean]

Use a logic analyser to review pin interactions. Pay attention to initial conditions. Consider pull up/down resistors to define state out of power up. Consider a POR circuit that holds reset low until all supplies have thresholded for several hundred milliseconds. ​

[TARHAN SAMAH]

Thankns mister clive to take time to answer.

so my problm as i understod is my data pins are floating i mean its not clear for lcd :

ENABLE RS 4 DATA isnt it ?

WHİCH pins İ HAVE to focus on on that prblm ??

because im using a keypad to send gnd to reset pi of the stm