;This code is here in case the system gets an NMI.  It clears the intterupt flag and returns.
badVec:      ; $FFE0 - IRQRVD2(134)
   php
   pha
   lda #$FF
            ;clear Irq
   pla
   plp
   rti

; File: SIM_8LED_CCAH.asm
; 09/16/2016

     PW 128         ;Page Width (# of char/line)
     PL 60          ;Page Length for HP Laser
     INCLIST ON     ;Add Include files in Listing

            ;*********************************************
            ;Test for Valid Processor defined in -D option
            ;*********************************************
   IF   USING_02
   ELSE
      EXIT         "Not Valid Processor: Use -DUSING_02, etc. ! ! ! ! ! ! ! ! ! ! ! !"
   ENDIF




;****************************************************************************
;****************************************************************************
; End of testing for proper Command line Options for Assembly of this program
;****************************************************************************
;****************************************************************************


         title  "6502 xSimul8r Program V 1.00 - 8 LED Active High"
         sttl


; bgnpkhdr
;***************************************************************************
;  FILE_NAME: SIM_8LED_CCAH.asm
;
;  DATA_RIGHTS: Western Design Center
;               Copyright(C) 1980-2016
;               All rights reserved. Reproduction in any manner,
;               in whole or in part, is strictly prohibited without
;               the prior written approval of The Western Design Center, Inc (WDC).
;
;               Information contained in this publication regarding
;               device applications and the like is intended through
;               suggestion only and may be superseded by updates.
;               It is your responsibility to ensure that your application
;               meets with your specifications.  No representation or
;               warranty is given and no liability is assumed by
;               Western Design Center, Inc. with respect to the accuracy
;               or use of such information, or infringement of patents
;               or other intellectual property rights arising from such
;               use or otherwise.  Use of WDC's products
;               as critical components in life support systems is not
;               authorized except with express written approval by
;               WDC.  No licenses are conveyed,implicitly or otherwise,
;                        under any intellectual property rights.
;
;
;
;  TITLE: 8LED_CCAH
;
;  DESCRIPTION: This File describes the WDC Simulator Example Program.
;
;
;
;  DEFINED FUNCTIONS:
;          badVec
;                   - Process a Bad Interrupt Vector - Hang!
;
;  SPECIAL_CONSIDERATIONS:
;
;
;  SHARED_DATA:
;          None
;
;  GLOBAL_MODULES:
;          None
;
;  LOCAL_MODULES:
;          See above in "DEFINED FUNCTIONS"
;
;  AUTHOR: David Gray
;
;  CREATION DATE: September 16, 2016
;
;  REVISION HISTORY
;     Name           Date         Description
;     ------------   ----------   ------------------------------------------------
;     David Gray   09/16/2016   1.00 Initial
;
;
; NOTE:
;    Change the lines for each version - current version is 1.00
;    See -
;         title  "6502 xSimul8r Program V 1.00 - 8 LED Active High"
;
;
;***************************************************************************
;endpkhdr


;***************************************************************************
;                             Include Files
;***************************************************************************
;None


;***************************************************************************
;                              Global Modules
;***************************************************************************
;None

;***************************************************************************
;                              External Modules
;***************************************************************************
;None

;***************************************************************************
;                              External Variables
;***************************************************************************
;None


;***************************************************************************
;                               Local Constants
;***************************************************************************
;
;   VIA_BASE:   equ   $f0
   VIA_BASE:   equ   $7FC0      ;; base address of VIA port on SXB
   VIA_ORB:   equ   VIA_BASE
   VIA_IRB:   equ   VIA_BASE
   VIA_ORA:   equ   VIA_BASE+1
   VIA_IRA:   equ   VIA_BASE+1
   VIA_DDRB:   equ   VIA_BASE+2
   VIA_DDRA:   equ   VIA_BASE+3
   VIA_T1CLO:   equ   VIA_BASE+4
   VIA_T1CHI:   equ   VIA_BASE+5
   VIA_T1LLO:   equ   VIA_BASE+6
   VIA_T1LHI:   equ   VIA_BASE+7
   VIA_T2CLO:   equ   VIA_BASE+8
   VIA_T2CHI:   equ   VIA_BASE+9
   VIA_SR:      equ   VIA_BASE+10
   VIA_ACR:   equ   VIA_BASE+11
   VIA_PCR:   equ   VIA_BASE+12
   VIA_IFR:   equ   VIA_BASE+13
   VIA_IER:   equ   VIA_BASE+14
   VIA_ORANH:   equ   VIA_BASE+15
   VIA_IRANH:   equ   VIA_BASE+15

      CHIP   65C02
      LONGI   OFF
      LONGA   OFF

   .sttl "6502 xSimul8r Demo Code"
   .page
;***************************************************************************
;***************************************************************************
;                    6502 xSimul8r Demo Code Section
;***************************************************************************
;***************************************************************************
;
;Example code to controll 8 LEDs driven from the W65C22 VIA Port B

      org   $2000      ;Our program code will be at $2000

   START:
      sei

      cld
      ldx   #$ff      ; Initialize the stack pointer
      txs

; First, we initialize the VIA chip registers and set Port B to OUTPUTS
      lda   #$ff
      sta   VIA_DDRB   ; set all as outputs

; Now we initialize the X register to use to count from 0 - 255 (FF)
      ldx #$00
;This is our loop where we get a value from $3000 in memory and load it
;into VIA Port B Output Register.  If ran all at once, this will cycle through memory
;from $3000 - $30FF.  The content at each memory address will be output to Port B
;which will be visable on the 8 LEDs as a binary equivalent.
;This exercise is meant to be done in the xSimul8r using single stepping.  The user can
;load the memory at $3000 with any data they wish.
LOADER:
      lda $3000,x      ; Load the value that is in memory at 3000 + x index.
      sta VIA_ORB      ; Display value on LEDs.  Value can be seen in ORB register of VIA
      inx            ; Increment the value of X by 1
      bne LOADER      ; Branch to the label "LOADER" if the value of the X-register is not $00

;After 256 loops, the program is done and we give control back to the simulator.       
   IRQHandler:
      pla
      rti

;This code is here in case the system gets an NMI.  It clears the intterupt flag and returns.
badVec:      ; $FFE0 - IRQRVD2(134)
   php
   pha
   lda #$FF
            ;clear Irq
   pla
   plp
   rti

This_project_end:
WDCMON_RAM_START   EQU   $7C00
ROMSPACE EQU WDCMON_RAM_START-This_project_end  ;gives space left in the ROM BEFORE WDCMON TABLES

   IF ROMSPACE<0
      EXIT         "Not Enough Memory for This Application - bumping into WDCMON! ! ! ! ! ! ! ! ! ! ! !"
   ENDIF


   bits:   db   1
   cnt:   db   0
   wraps:   dw   0
   delay:   db   10

;***************************************************************************
;***************************************************************************
; New for WDCMON V1.04
;  Needed to move Shadow Vectors into proper area
;***************************************************************************
;***************************************************************************
   SH_vectors:   section
Shadow_VECTORS   SECTION OFFSET $7EFA
               ;65C02 Interrupt Vectors
               ; Common 8 bit Vectors for all CPUs

      dw   badVec      ; $FFFA -  NMIRQ (ALL)
      dw   START      ; $FFFC -  RESET (ALL)
      dw   IRQHandler   ; $FFFE -  IRQBRK (ALL)

           ends


;***************************************************************************

vectors   SECTION OFFSET $FFFA
               ;65C02 Interrupt Vectors
               ; Common 8 bit Vectors for all CPUs

      dw   badVec      ; $FFFA -  NMIRQ (ALL)
      dw   START      ; $FFFC -  RESET (ALL)
      dw   IRQHandler   ; $FFFE -  IRQBRK (ALL)

           ends

           end