Arduino: How to control a HD44780 based character LCD

Many characters LCD displays use so called HD44780 based protocol on interface. This is more like as standard but i recommend to check datasheet from vendor. There can be small modifications and/or difference in timing. Especially timing is important. If communication rate is too quick, then LCD can drop data or misbehave depending on internal state. I recommend to check busy flag, if possible. If not then correct delay should be applied between commands.

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