# Can Jacdac be used for connecting together multiple Micro:bits?
**URL:** https://forum.makecode.com/t/can-jacdac-be-used-for-connecting-together-multiple-micro-bits/17677
**Category:** Jacdac
**Created:** [January 30, 2023, 11:10pm UTC](https://forum.makecode.com/t/can-jacdac-be-used-for-connecting-together-multiple-micro-bits/17677 "2023-01-30T23:10:31Z")
**Posts on this page:** 7
**Page:** 1
### Author:  [@sjmurdoch](https://forum.makecode.com/u/sjmurdoch)
#### Post date: [January 30, 2023, 11:10pm UTC](https://forum.makecode.com/t/can-jacdac-be-used-for-connecting-together-multiple-micro-bits/17677/1 "2023-01-30T23:10:31Z")
The Jacdac examples I’ve seen are all about connecting sensors and buttons to a Micro:bit. That’s great but I am interested in connecting Micro:bits to each other, initially two but perhaps more. Is this possible? If so can this be done with existing blocks or would it require a MakeCode extension to be created?
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### Author:  [@randomuser](https://forum.makecode.com/u/randomuser)
#### Post date: [January 31, 2023, 1:11am UTC](https://forum.makecode.com/t/can-jacdac-be-used-for-connecting-together-multiple-micro-bits/17677/2 "2023-01-31T01:11:40Z")
What do you mean by ‘connected’? Like multiplayer?
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### Author:  [@sjmurdoch](https://forum.makecode.com/u/sjmurdoch)
#### Post date: [January 31, 2023, 1:33am UTC](https://forum.makecode.com/t/can-jacdac-be-used-for-connecting-together-multiple-micro-bits/17677/3 "2023-01-31T01:33:01Z")
I mean being able to send bytes to each other, half-duplex. I am thinking of simulating how a smart card and smart card reader talk to each other, which is a serial half-duplex protocol.
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### Author:  [@randomuser](https://forum.makecode.com/u/randomuser)
#### Post date: [January 31, 2023, 6:07pm UTC](https://forum.makecode.com/t/can-jacdac-be-used-for-connecting-together-multiple-micro-bits/17677/4 "2023-01-31T18:07:12Z")
Ah, sorry! I wouldn’t know then!
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### Author:  [@bsiever](https://forum.makecode.com/u/bsiever)
#### Post date: [March 14, 2024, 1:17am UTC](https://forum.makecode.com/t/can-jacdac-be-used-for-connecting-together-multiple-micro-bits/17677/5 "2024-03-14T01:17:42Z")
@sjmurdoch This isn’t using Jacdac, but it is possible to redirect the serial port (from USB to other pins) to have micro:bits communicate. Of course, this may not be ideal for a demonstration if the demo relies on serial (console) messages to show what’s happening.
On a related note, there are/were some interesting networking ideas in “Networking with the micro:bit” by Cigdem Sengul and Anthony Kirby. It looks like it’s still freely available via a GitHub repository: [https://github.com/nominetresearch/microbit-networking-book](https://github.com/nominetresearch/microbit-networking-book). The wired serial redirect example is here: [https://github.com/nominetresearch/microbit-networking-book/blob/master/wiredcommunication/wiredcommunication.md](https://github.com/nominetresearch/microbit-networking-book/blob/master/wiredcommunication/wiredcommunication.md) . (Also has a Python edition: [https://github.com/nominetresearch/microbit-networking-book-python](https://github.com/nominetresearch/microbit-networking-book-python)) .
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### Author:  [@sjmurdoch](https://forum.makecode.com/u/sjmurdoch)
#### Post date: [March 25, 2024, 12:21am UTC](https://forum.makecode.com/t/can-jacdac-be-used-for-connecting-together-multiple-micro-bits/17677/6 "2024-03-25T00:21:20Z")
Thanks @bsiever. The book you referenced is quite interesting although doesn’t seem exactly what I’m looking for (which might not exist). The wired examples seem to be unidirectional whereas I’m looking for a simulation of the half-duplex smart card protocol.
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### Author:  [@bsiever](https://forum.makecode.com/u/bsiever)
#### Post date: [March 25, 2024, 1:00am UTC](https://forum.makecode.com/t/can-jacdac-be-used-for-connecting-together-multiple-micro-bits/17677/7 "2024-03-25T01:00:47Z")
@sjmurdoch What’s the specific smart card or specific protocol?
Here are some examples of bidirectional UART communication:
- Pretty detailed/comprehensive video: [https://www.youtube.com/watch?v=MYoMM1FY6yM](https://www.youtube.com/watch?v=MYoMM1FY6yM) (Actual micro:bit demo of 2-way communication at about 900 seconds : [https://youtu.be/MYoMM1FY6yM?t=900](https://youtu.be/MYoMM1FY6yM?t=900))
- Here’s a tutorial on micro:bit to Arduino communication using the same trick: [https://samndave.org.uk/ourdoc/2020/12/26/microbit-serial-communications/](https://samndave.org.uk/ourdoc/2020/12/26/microbit-serial-communications/) (I haven’t tested this)