MC68HC11F1_13 Datasheet, PDF (28/158 Pages) Freescale Semiconductor, Inc – Technical Data

Freescale Semiconductor, Inc.
JSR, JUMP TO SUBROUTINE
MAIN PROGRAM
PC
$9D = JSR
DIRECT
dd
RTN NEXT MAIN INSTR
PC
INDXD,X
RTN
MAIN PROGRAM
$AD = JSR
ff
NEXT MAIN INSTR
PC
INDXD,Y
RTN
MAIN PROGRAM
$18 = PRE
$AD = JSR
ff
NEXT MAIN INSTR
MAIN PROGRAM
PC
$BD = JSR
hh
EXTEND
ll
RTN NEXT MAIN INSTR
BSR, BRANCH TO SUBROUTINE
MAIN PROGRAM
PC
$8D = BSR
rr
RTN NEXT MAIN INSTR
RTS, RETURN FROM SUBROUTINE
SUBROUTINE
PC
$39 = RTS
SP-2
SP-1
SP
SP-2
SP-1
SP
SP
SP+1
SP+2
STACK
RTN_H
RTN_L
STACK
RTN_H
RTN_L
STACK
RTN_H
RTN_L
RTI, RETURN FROM INTERRUPT
INTERRUPT PROGRAM
PC
$3B = RTI
STACK
SP
SP+1 CONDITION CODE
SP+2
ACMLTR B
SP+3
ACMLTR A
SP+4 INDEX REGISTER (X_H)
SP+5 INDEX REGISTER (X_L)
SP+6
SP+7
SP+8
SP+9
INDEX REGISTER (Y_H)
INDEX REGISTER (Y_L)
RTN_H
RTN_L
SWI, SOFTWARE INTERRUPT
MAIN PROGRAM
PC
$3F = SWI
RTN
WAI, WAIT FOR INTERRUPT
MAIN PROGRAM
PC
$3E = WAI
RTN
STACK
SP-9
SP-8 CONDITION CODE
SP-7
ACMLTR B
SP-6
ACMLTR A
SP-5 INDEX REGISTER (X_H)
SP-4 INDEX REGISTER (X_L)
SP-3 INDEX REGISTER (Y_H)
SP-2 INDEX REGISTER (Y_L)
SP-1
RTN_H
SP
RTN_L
LEGEND:
RTN
RTN_H
RTN_L
dd
ff
hh
ll
rr
Address of next instruction in main program to be
executed upon return from subroutine.
Most significant byte of return address.
Least significant byte of return address.
Shaded cells show stack pointer position after
operation is complete.
8-bit direct address ($0000-$00FF) (high byte
assumed to be $00).
8-bit positive offset $00 (0) to $FF (256) is added
to index.
High-order byte of 16-bit extended address.
Low-order byte of 16-bit extended address.
Signed-relative offset $80 (-128) to $7F (+127)
(offset relative to the address following the
machine code offset byte).
Figure 3-2 Stacking Operations
When a subroutine is called by a jump to subroutine (JSR) or branch to subroutine
(BSR) instruction, the address of the instruction after the JSR or BSR is automatically
pushed onto the stack, least significant byte first. When the subroutine is finished, a
return from subroutine (RTS) instruction is executed. The RTS pulls the previously
stacked return address from the stack, and loads it into the program counter. Execu-
tion then continues at this recovered return address.
CENTRAL PROCESSING UNIT
MC68HC11F1
3-4
For More Information On This Product,
TECHNICAL DATA
Go to: www.freescale.com