# Adding more pins via i²c (in Blocks)
**URL:** https://forum.makecode.com/t/adding-more-pins-via-i-c-in-blocks/31715
**Category:** micro:bit
**Created:** [November 14, 2024, 11:05pm UTC](https://forum.makecode.com/t/adding-more-pins-via-i-c-in-blocks/31715 "2024-11-14T23:05:24Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@Oli](https://forum.makecode.com/u/Oli)
#### Post date: [November 14, 2024, 11:05pm UTC](https://forum.makecode.com/t/adding-more-pins-via-i-c-in-blocks/31715/1 "2024-11-14T23:05:24Z")
We’ve had a couple of projects where pins are really tight. I’ve looked at multiplexing and using the LED pins and using an i2c screen but they are all less than perfect.
I recently found that there are a couple of micro controllers that allow you to add a bank of pins over i2c. I’ve bought a PCF8574 but there’s also the MCP23017. It seems like if you’re using Python, reading/writing binary states over i2c is really simple, but my daughter isn’t there yet.
Does anyone know of a block-friendly way to do this sort of thing?
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### Author:  [@Don](https://forum.makecode.com/u/Don)
#### Post date: [November 17, 2024, 7:45pm UTC](https://forum.makecode.com/t/adding-more-pins-via-i-c-in-blocks/31715/2 "2024-11-17T19:45:54Z")
To be able to write to the pins as if they are extra pins you would need to write a TypeScript extension.
However, you could try using the i2c interface that is given.
If this is still a bit too involved you would write a set of functions for her that do the hard stuff.
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### Author:  [@Don](https://forum.makecode.com/u/Don)
#### Post date: [November 17, 2024, 7:46pm UTC](https://forum.makecode.com/t/adding-more-pins-via-i-c-in-blocks/31715/3 "2024-11-17T19:46:20Z")
It looks like there is already an extension written. I can’t say if it works or not.
> **[GitHub - rsp-esl/pxt-pcf8574: PCF8574: A Makecode-Microbit extension](https://github.com/rsp-esl/pxt-pcf8574/tree/master)**
>
> master
I tried to just import it and it didn’t work. You may have to fiddle with it a bit.
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### Author:  [@Don](https://forum.makecode.com/u/Don)
#### Post date: [November 17, 2024, 8:43pm UTC](https://forum.makecode.com/t/adding-more-pins-via-i-c-in-blocks/31715/4 "2024-11-17T20:43:34Z")
Here is an example. My Maqueen Plus V2 robot has the headlights on the i2c bus. I can use the blocks, but here is how I would use the i2c interface directly to get to the LED headlights.
