Torubleshooting LCD2004

Now I am replacing the seemingly problematic LCD2004 by a LCD1606.  This time all 2 LCDs and one keypad work together.

I can display both LCDs and then test inputting 4 keys.  The good thing is that the keypad does not corrupt the LCD1602, though corrupting LCD1604's last line.

This also shows that the LCD2004 is indeed problematic.

.END