JSB Instruction

None

Purpose:

Transfer control to subroutine.

Format:

opcode displ.bx

Operation:

-(SP) <- PC;
PC <- dst;

Condition
Codes:

N <- N;
Z <- Z;
V <- V;
C <- C;

Exceptions:

Opcodes:

JSB

Jump to Subroutine

Description:

The PC is pushed on the stack as a long word. The sign-extended displacement operand is added to the PC and the PC is replaced by the result.

Notes:

1.: Since the operand specifier conventions cause the evaluation of the destination operand before saving the PC, JSB can be used for coroutine calls with the stack used for linkage. The form of such a call is JSB @(SP)+.
2.: See also RSB.