# WM_SetPortCallback

## Syntax

      #include <nitro/wm.h>

      WMErrCode WM_SetPortCallback(
              u16             port ,
              WMCallbackFunc  callback ,
              void*           arg
      );

## Arguments

port | Port number. Use a value from 0-15.
callback | Specifies the callback function to be called when receiving the communication frames. This callback is called from within the interrupt handler.
arg | Argument passed to the callback function.

## Return Values

Returns the results of the `WMErrCode` enumerated type process.

## Description

Sets the callback function that is called when the data for the specified port is received This is a synchronous function that promptly returns the `WM_ERRCODE_SUCCESS` return value when the process succeeds.

## See Also

`WM_SetMPDataToPort`, `WMPort`

## Revision History

2005/06/08 Added statement about callbacks being called from the interrupt handler.
2005/03/02 Added statement about range that can be specified with the port argument.
2004/10/22 Changed return value type.
2004/08/11 Initial version

CONFIDENTIAL