--- title: iButton slug: zero/ibutton description: iButton module's functionality and hardware image: https://archbee-image-uploads.s3.amazonaws.com/3StCFqarJkJQZV-7N79yY/kxsGC_NM-WSR-fkouYYGK_ibutton.png docTags: createdAt: 2022-09-19T13:49:38.000Z --- ![](https://api.archbee.com/api/optimize/3GUDYkC5JgUWgo6RW8piO-p0FVsy724Lu_Y_rim48S7-20241025-124007.png) Flipper Zero supports a 1-Wire device communication protocol, which is implemented in small electronic keys known as iButton keys. These keys are used for access control, temperature measurements, humidity measurements, storing cryptographic keys, etc. Flipper Zero can read, write, and emulate iButton access control keys with its built-in iButton module, which supports Dallas, Cyfral, and Metakom key protocols. :::Iframe{iframeHeight="0" code="
Insert a microSD card to use the iButton app
Before using the iButton app, make sure to update your Flipper Zero firmware with a microSD card inserted since Flipper Zero stores databases on a microSD card. For more information about the update process, visit the Firmware update page.
"} ::: On this page, you’ll find an overview of the iButton application and learn more about the hardware behind the iButton module. *** # iButton menu You can access the iButton application from the Main Menu. In the application, you can read, save, edit, write, and emulate iButton keys. ![](https://api.archbee.com/api/optimize/3StCFqarJkJQZV-7N79yY/mcomeNOquOxGPZ1b68p0k_monosnap-miro-2023-10-16-12-20-54.jpg "iButton application menu") - [Read](https://docs.flipper.net/zero/ibutton/read)**:** detects key’s type, reads and saves key’s unique number. - **Saved:** emulates, edits, and writes saved keys. - [Add Manually](https://docs.flipper.net/zero/ibutton/add-manually)**:** generates keys with unique numbers that can be emulated. *** # iButton hardware :::Iframe{code="
Not all iButton devices can be detected by Flipper Zero
Various iButton devices may have the same form factor, however, only access control keys can be detected by Flipper Zero.
" iframeHeight="0"} ::: Flipper Zero has a built-in iButton module consisting of an iButton pad and three [spring-loaded pogo pins](https://en.wikipedia.org/wiki/Pogo_pin) that are located on the iButton PCB. ![](https://cdn.flipperzero.one/Monosnap_Miro_2022-09-28_19-27-31.png "iButton module’s pins") Two pins are assigned to data transfer and have output to the GPIO pin 17. The remaining middle pin is ground. ::Image[]{src="https://cdn.flipperzero.one/Monosnap_Miro_2022-09-28_19-29-05.png" size="82" width="2014" height="1104" caption="iButton data pins have output to the GPIO pin 17" position="center" darkWidth="2014" darkHeight="1104" showCaption="true"} The flat part of the pad allows connecting an iButton key (Slave) with Flipper Zero (Master). The left data pin and the middle ground pin are used for reading and writing iButton keys. ::Image[]{src="https://cdn.flipperzero.one/Monosnap_Miro_2022-09-29_18-31-34.png" size="90" width="1638" height="802" caption="Pins used for reading and writing" position="center" darkWidth="1638" darkHeight="802" showCaption="true"} The protruding part of the pad allows connecting Flipper Zero (Slave) with an iButton reader (Master). The right data pin and the middle ground pin are used for emulation of iButton keys. ::Image[]{src="https://cdn.flipperzero.one/Monosnap_Miro_2022-09-29_18-27-39.png" size="90" width="1772" height="890" caption="Pins used for emulation" position="center" showCaption="true"} *** ::::LinkArray{contentSource="CUSTOM"} :::LinkArrayItem{headerType="IMAGE" headerImage="https://api.archbee.com/api/optimize/3StCFqarJkJQZV-7N79yY/kxtsdU0BA4TeD_rPB0DzR_reading-ibutton-keys-block.png"} [Reading iButton keys](https://docs.flipper.net/zero/ibutton/read) ::: :::LinkArrayItem{headerType="IMAGE" headerImage="https://api.archbee.com/api/optimize/3StCFqarJkJQZV-7N79yY/auVfSh9O_eunQEFC421NT_adding-ibutton-keys-manually-block.png"} [Adding iButton keys manually](https://docs.flipper.net/zero/ibutton/add-manually) ::: :::LinkArrayItem{headerType="IMAGE" headerImage="https://api.archbee.com/api/optimize/3StCFqarJkJQZV-7N79yY/0ZDwjHr-UPSLC8FcHihOc_writing-data-to-ibutton-blanks-block.png"} [Writing data to iButton keys](https://docs.flipper.net/zero/ibutton/write) ::: :::LinkArrayItem{headerType="IMAGE" headerImage="https://api.archbee.com/api/optimize/3StCFqarJkJQZV-7N79yY/FaM11lt8jMe1TQWYp52A6_pflnlgh9s-xtykklkskb1-monosnap-miro-2022-10-25-19-39-43.webp"} [Flipper Zero schematics](https://docs.flipper.net/zero/development/hardware/schematic) ::: :::LinkArrayItem{headerType="IMAGE" headerImage="https://api.archbee.com/api/optimize/3StCFqarJkJQZV-7N79yY/7_VPROKgReSBtiBsWiw5z_qk2fdzhhnl66ou16o74iw-monosnap-miro-2022-10-25-19-31-25.webp"} [iButton application source code](https://github.com/flipperdevices/flipperzero-firmware/tree/dev/applications/main/ibutton) ::: ::::