# NFC Read Tag

Uses the device NFC antenna for reading data from HF tags when in close proximity.

Action available for the following operating systems:

![](/files/kfMeq0OanEe5OOx5RmUn)

### Parameters

* **Tag Type** numeric - The type of tags to read data. It can be one of:
  * 1 - **Mifare Classic**
  * 2 - **Mifare Ultralight**
  * 3 - **ISO 15693**
* **Option** numeric - Select what to read. It can be one of:
  * 1 - **Read ID**
  * 2 - **Read Data**
* **Coded** numeric - Converts non-printable chars into its ASCII code enclosed in ‘<’ and ‘>’. This is useful for debugging. It can be one of:
  * 1 - **Yes**
  * 2 - **No**
* **Block Index** numeric - Block index to read.
* **Nbr of Bytes** numeric - The number of bytes to read starting in the specified Block Index.
* **Target** string - The control or variable that will receive the tag ID or tag Data depending on the Option parameter.

{% hint style="warning" %}
For these last two parameters, it is important to consider that they are only available if **Option** is set to **2 - Read Data**.
{% endhint %}

{% hint style="info" %}
On iOS currently read/write is only supported for ISO 15693\
(TagID can be read for other Tag Types)
{% endhint %}

{% hint style="info" %}
Tag IDs are returned in MSB (Most Significant Byte), so if you need to use them in LSB you need to reverse the returned ID bytes.
{% endhint %}

{% hint style="info" %}
On Android, specifying **Tag Type = 0** allows to use the **Read ID option** for any tag type supported by Android.
{% endhint %}


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