---
active: false
tags: project
created: 2026-03-08 20:25
---
## Goal

Build an I2C based MFRC522 reader. 

- Use RJ45 connectors
- Use DIP switches to set address
## Tasks

- [ ] Clone the SPI based board ➕ 2026-03-08
- [ ] Redesign the SPI based board to be I2C ➕ 2026-03-08
## References

- [DIP Switches for Setting I2C address](https://www.ctscorp.com/Files/DataSheets/Switches/DIP-Switches/CTS-Switches-DIP-219-Series-Datasheet.pdf)
- [DigiKey DIP switches](https://www.digikey.com/en/products/detail/cts-electrocomponents/219-5MST/223200)
- [MFRC522 Data Sheet](https://www.nxp.com/docs/en/data-sheet/MFRC522.pdf)
- [I2C Specification](https://www.nxp.com/docs/en/user-guide/UM10204.pdf)