Programming the Microprocessor

Write your source code.

Download and Install Notepad++ from https://notepad-plus-plus.org/
Create a new folder (direcotry) Called VASM6502
Open Notepad++ and select File and then select New. (Opens a new window)
Select Language and then select the Letter A then select Assembly. 
Assembly Language file uses the .s extension or .asm
Select File again and then Save AS to the folder VASM6502 [enter a file name for your program] 
Make sure it has the .asm extension (yourfilename.asm) then click Save.
Make sure you have line numbering turned On. Found under Settings/Preferences/Editing/Display line number.  
Cut and paste the example code below into Notepad++ at line #1 
Select File again and then Save  

Example code:

      STX #$6ffc ; capture x reg
      LDX #$55    ; set counter to binary 10101010
count EQU *
      LDA #$0f   ; Turn on half of the LED's 00001111
      STA $6000  ; Write value to VIA chip
      DEX	 ; Decrease the X register by 1
      LDA #$f0   ; Turn on other half of the LED's 11110000
      BNE count
      LDX $6ffc  ; Restore X reg to orginal value
      LDA #$00   ; turn off all LED's 00000000
      STA $6000  ; Write value to VIA chip

Compile your source code Windows 10.

Download the application VASM from Dr. Volker Barthelmann´s Compiler Page: http://www.compilers.de/vasm.html
Select Binaries of vasm for 6502 for x86-64 (Mac, Windows and Linux): http://www.ibaug.de/vasm/vasm6502.zip
Move vasm6502.zip to your new folder VASM6502 and extract the zip file in that folder.
Open the new folder called vasm6502_oldstyle and select your operating system. I will be using Windows folder. (Win\Win10)
Open WIN folder then Win10 folder and copy the relative path.
C:\Users\this-PC\Documents\VASM-6502\vasm6502_oldstyle\win\win10
VASM6502 compiler is a command line program (CMD) so you need to use the CMD prompt terminal.
Open CMD terminal and change directory to the VASM6502 directory.  
CD Users\this-PC\Documents\VASM-6502\vasm6502_oldstyle\win\win10
 

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