Inside Macintosh: Memory /

Chapter 1 - Introduction to Memory Management / Memory Management Reference

Memory Management Routines / Setting and Restoring the A5 Register

SetA5

In interrupt code that accesses application global variables, use the SetA5 function first to restore a value previously saved using SetCurrentA5, and then, at the end of the code, to restore the A5 register to the value it had before the first call to SetA5.

FUNCTION SetA5 (newA5: LongInt): LongInt;

newA5

The value to which the A5 register is to be changed.

DESCRIPTION

The SetA5 function performs two tasks: it returns the address in the A5 register when the function is called, and it sets the A5 register to the address specified in newA5.