just to clearify write times.

minimum times for signals are

Enable pulse width 450ns
Register select and read / write set up times 140ns
Data setup time 195ns

there is no maximum times for these signals.

but having programmed a few different lcd modules, i believe
the real question is how much time must pas between each byte
of data sent to the device.

the clear display command requires between 82us and 1.6ms

Return home 40us to 1.6ms

all other commands 40us

just a note about return home, i use the set CG ram address
to location zero, it only takes 40us.

michael