# packet\_rx

This class is a wrapper class for TWENET's `tsRxDataApp` structure.

This class object is a wrapper class for [behavior](/latest_en/api-reference/behavior.md) callback function or by [`on_rx_packets()`](/latest_en/api-reference/sys_callbacks/on_rx_packet.md).

In `packet_rx`, in particular, the data payload of the packet can be handled by the `smplbuf` container, and utility functions such as `expand_bytes()` simplify the payload interpretation description.

{% hint style="info" %}
At this time, we have implemented methods and other interfaces, mainly those required for the simple relay network `<NWK_SIMPLE>`.
{% endhint %}

## Methods

### get\_payload()

```cpp
smplbuf_u8_attach& get_payload()
```

Get the data payload of the packet.

{% hint style="info" %}
If `<NWK_SIMPLE>` is used, there is header data for `<NWK_SIMPLE>` at the beginning. The container referred to in the return will be a sub-array excluding the header. If you want to refer to the header part, refer to the `tsRxDataApp` structure by `get_psRxDataApp()`.
{% endhint %}

### get\_psRxDataApp()

```cpp
const tsRxDataApp* get_psRxDataApp() 
```

Obtain the receiving structure of the TWENET C library.

### get\_length()

```cpp
uint8_t get_length()
```

Returns the data length of the payload. The value is the same as `.get_payload().size()`.

### get\_lqi()

```cpp
uint8_t get_lqi()
```

Obtain the LQI value (Link Quality Indicator).

{% hint style="info" %}
LQI is a value that indicates the quality of radio communication, expressed as a number from 0 to 255.

Incidentally, if you want to evaluate it in several levels, you can classify it as follows: less than 50 (bad - less than 80 dbm), 50 to 100 (somewhat bad), 100 to 150 (good), 150 or more (near the antenna), and so on. Please note that these are only guidelines.
{% endhint %}

### get\_addr\_src\_long(), get\_addr\_src\_lid()

```cpp
uint32_t get_addr_src_long()
uint8_t get_addr_src_lid()
```

Get the address of the sender.

`get_addr_src_long()` is the serial number of the sender and MSB(bit31) is always 1.

`get_addr_src_lid()` is the logical ID of the sender and takes values from `0x00`-`0xFE` (the logical ID specified by `<NWK_SIMPLE>`).

### get\_addr\_dst()

```cpp
uint32_t get_addr_dst()
```

Gets the destination address.

The destination address is specified by the source, and the range of values varies depending on the type of destination.

| Value                                              | Explanation   |
| -------------------------------------------------- | ------------- |
| MSB (bit31) is set.                                | `0x00`-`0xFF` |
| Logical ID (8bit) is specified as the destination. | `0x00`-`0xFF` |

### is\_secure\_pkt()

```cpp
bool is_secure_pkt()
```

Returns `true` for encrypted packets and `false` for plaintext.

### get\_network\_type()

```cpp
uint8_t get_network_type() 
```

Returns network type of the packet identified by Network BEHAVIOR.

| Value                   | Explanation                  |
| ----------------------- | ---------------------------- |
| `mwx::NETWORK::LAYERED` | packets from `<NWK_LAYERED>` |
| `mwx::NETWORK::SIMPLE`  | packets from `<NWK_SIMPLE>`  |
| `mwx::NETWORK::NONE`    | neworkless packets           |
| others                  | error or unknow packet type  |


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://mwx.twelite.info/latest_en/api-reference/classes/packet_rx.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.