# CARD_LockBackup

## C Specification

  `#include <nitro/card.h>`
  `void CARD_LockBackup(u16 lock_id);`

## Arguments

lock_id | The ID that is used for locking a card. This ID is obtained by the `OS_GetLockID` function.

## Return Values

None

## Description

This function locks the access bus to the CARD backup device. If another module (with another ID) has already locked the bus, `CARD_LockRom` waits until the bus returns to an unlocked state before it executes The function will return control after locking the card.

## Caution

All functions that access a CARD backup device must first lock the access bus.
You cannot access a CARD ROM device and a backup device simultaneously.
While one bus is locked, other bus locks are forced to wait.

## See Also

`OS_GetLockID`, `OS_LockCard`, `OS_LockCartridge`, `CARD_UnlockBackup`

## Revision History

09/06/2004 Added the description for the prototype.
08/31/2004 Added the description of function always succeeding.
07/23/2004 Changed lock ID type from u32 to u16.
07/13/2004 Addition concerning exclusive control of CARD ROM device and backup device
07/10/2004 Initial version.