Hi,

Richard was right, Data must be stable, if EN was set high.

But furthermore the initialization was not sufficient in any case.

The correct initilization sequence can be found on page 46 of the HD44780U data sheet:

power on
wait >40ms
write nibble 03
wait >4.1ms
write nibble 03
wait >100µs
write nibble 03
write nibble 02

now in 4 bit mode and always 2 nibbles must be send and BF can be checked.


Peter