NAME

SetSR: get and/or set processor status register

SYNOPSIS

oldSR = SetSR(newSR, mask)
D0 D0 D1

ULONG SetSR(ULONG, ULONG);

FUNCTION

This function provides a means of modifying the CPU status register in a "safe" way (well, how safe can a function like this be anyway?). This function will only affect the status register bits specified in the mask parameter. The prior content of the entire status register is returned.

INPUTS

newSR: new values for bits specified in the mask. All other bits are not effected.
mask: bits to be changed

RESULT

oldSR: the entire status register before new bits

EXAMPLE

To get the current SR:

currentSR = SetSR(0,0);

To change the processor interrupt level to 3:

oldSR = SetSR($0300,$0700);

Set processor interrupts back to prior level:

SetSR(oldSR,$0700);