THE HC11:

            A        B
        [========|========]
D       [=================]


X       [=================]

Y       [=================]

    ; registers A and B are just the
    ; top and bottom halves of D.
    ; X and Y are index registers.
    ; A and B are 8 bits each,
    ; D, X, and Y are 16 bits.
    ; This gives you only three
    ; registers to play with... so you 
    ; will become friends with the 
    ; stack very soon.
NOTES:
    * If you modify D, A and B will be modified.
    * Integer constants work much like in C.
      74, 0112, 0x4A, 0X4a, and 'J' are all the
      same value to the assembler.
    * Labels must be in the first column.  
	Everything else should be indented by
	at least one block.

--------------------+-------------------
HC11 INSTRUCTION        MAL "EQUIVALENT"
--------------------+-------------------
   jsr                    jal
    ; jump subroutine

   rts                    jr
    ; except that rts is inherent, i.e.
    ; it knows where you want to go.
    ; you don't have to provide a
    ; destination like in MAL's jr $ra
   jmp                    j

   bra                    b
    ; branches are fairly similar, except
    ; you should compare before branching
    ; with cmpa,cmpb,cba,cpd,cpx,cpy

THE STACK:
    psha,pshb,pshx,pshy
    pula,pulb,pulx,puly
    ; pushing and pulling from the stack
    ; automatically uses the built-in
    ; system stack and incra- or decraments
    ; the stack pointer for you


Check Chapter 6 in the M68HC11 Reference Manual for more details.


Happy pushing,
alex;
updated 11/19/01 (talby)