prog6.asm

主要是8051源代码

;  PROG6 - Accessing Scratchpad RAM
;
;  This Program Reads and Writes to the 128 Bytes of Scratchpad RAM available
;   at the start of the 8051's Data Space.
;
;  This program will run in the UMPS simulator for a DS80C320.
;
;  Myke Predko
;  98.02.09
;
;  Hardware Notes:
;   This program is only meant to run on the Simulator

;  Variable Declarations
;   R0, R1 and R2 Used for Data/Variable Storage
Var1 EQU 8                      ;  Define Variables to be Used in the Program
Var2 EQU 9

VarR0 EQU 0                     ;  This is the Same as R0 in Bank 0

;  Mainline
 org 0                          ;  Execution Starts Here

  mov    R0,#123                ;  Load Bank Register 0 with 123
                                ;   To Initialize the Value for Later

  mov    Var1,#12               ;  Initialize the RAM Variables
  mov    Var2,#34

;  Var1 = Var1 | Var2           - Create Assembler Code for this
;					    Statement

  mov    A,Var1                 ;  Load Accumulator with Contents of Var1
  orl    A,Var2                 ;  Bitwise OR Accumulator with Contents of Var2
  mov    Var1,A                 ;  Store the Result

  mov    VarR0,#Var1            ;  R0 Now Points to Var1

  mov    @R0,#0                 ;  Clear the Values that R0 is Pointing To


Loop:                           ;  Loop Here Forever when Finished
  ajmp   Loop