Using HD44780 on Raspberry Pi – part 7: 40×4 and I2C

We have direct mode, buffered mode, GPIO access. What is missing ? I2C for twin-lcd. Lets get to work.

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Previous parts



Piader – virtual lcd

We have our game and we have our vlcd. Lets mix it together.

Our goal is to create one vlcd 16×6 for game and small 4×4 for displaying score. Something like this:


Why right alignment ? Because I have short wires 🙂

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Virtual display – part 2: offsets

We have a simple virtual display. It can join lcds in one virtual area. But there is one catch. Look at the following layouts (red area is virtual lcd):


No problem. But what about:


… we can’t do it ! And what if we want to use this small 4×4 as second virtual display ? We can’t !

When we add lcd its added at any (x,y) but always starts from (0,0). Lets add an offset, so we can specify area.

Update – error in code. see at the bottom

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