Zilog Z16F2810 - Manual (Page 140)

LINK Instruction UM018809-0611
124
ZNEO
®
CPU Core
User Manual
LINK
Definition
Link Frame Pointer
Syntax
LINK #uimm8
Operation
SP
 SP
– 4

(SP)

R14

R14
SP
SP
SP – uimm8
Description
This instruction establishes an argument frame pointer in register R14 and allocates local variable
space on the stack. The FP register can then be used for efficient indirect access to subroutine
arguments and variables.
The LINK instruction performs the following steps:
1. Preserve the existing contents of R14 by pushing it onto the stack.
2. Load the contents of the stack pointer into R14.
3. Subtract the value contained in the source operand from the stack pointer.
Flags
Flags are not affected by this instruction.
Syntax and Opcodes
Instruction, Operands Word 0 Word 1 Word 2
LINK #uimm8 {08H, uimm8}