# WXC_RegisterCommonData

## Syntax

  `#include <nitro/wxc.h>`
  `void WXC_RegisterCommonData(u32 ggid, WXCCallback callback, u8 *send_ptr, u32 send_size, u8 *recv_ptr, u32 recv_size);`

## Arguments

ggid | GGID of the data to register.
callback | User callback function. It is invoked when the data exchange is complete.
send_ptr | Pointer to the data to register.
send_size | Size of the data to register.
recv_ptr | Pointer to the receive buffer.
recv_size | Size of the receive buffer.

## Return Values

None.

## Description

This function registers a GGID to search for other units executing chance encounter communications, and sets data to be exchanged.
The WXC library uses the GGID registered using this function to search for other units executing chance encounter communications and automatically exchanges data.
You can use the `WXC_SetInitialData` function to reconfigure the data set by this function.

## Note

The WXC library does not use the beacon's GGID value that is assigned by the MP communication parent. The value used has special bits (WXC_GGID_COMMON_BIT: 0x80000000) added to the GGID that indicate common chance encounter communications.Note this point when monitoring actual radio wave status using `WmTestTool`.

## See Also

`WXC_SetInitialData`

## Revision History

2009/09/29 Added Note about special bits that are added to the beacon's GGID.
2009/04/21 Initial version.

CONFIDENTIAL