Ves.h

This is an attempt to assemble code that is used
often in the homebrew programs, such as the necessary
cartridge start byte, simplification to set the ISAR
and others.

Use it in your project and add include "ves.h"
to be able to call these macros easily in your program
code.

; VES.H
; Fairchild Channel F Header
; Version 1.01, 2/NOVEMBER/2004

VERSION_CHANNELF	= 101
VERSION_VES		= 101

; THIS IS A PRELIMINARY RELEASE OF *THE* "STANDARD" VES.H
; THIS FILE IS EXPLICITLY SUPPORTED AS A DASM-PREFERRED COMPANION FILE
; PLEASE DO *NOT* REDISTRIBUTE THIS FILE!
;
; This file defines hardware registers and memory mapping for the
; Fairchild Channel-F. It is distributed as a companion machine-specific support package
; for the DASM compiler. Updates to this file, DASM, and associated tools are
; available at at http://www.atari2600.org/dasm
;
; Many thanks to the original author(s) of this file, and to everyone who has
; contributed to understanding the Channel-F.  If you take issue with the
; contents, or naming of registers, please write to me (atari2600@taswegian.com)
; with your views.  Please contribute, if you think you can improve this
; file!
;
; Latest Revisions...
; 1.01   2/NOV/2004	Kevin Lipe's version (combined macro/header)
;			renamed to VES.H
;			alternates provided for deprecated equates
;			ALL hardware/BIOS equates now in uppercase and prefixed
; 1.00  31/OCT/2004	- initial release



; Please contribute Channel-F header code to atari2600@taswegian.com



INCLUDE_DEPRECATED                 ; remove to DISABLE deprecated equates


;-------------------------------------------------------------------------------
; BIOS Calls
;------------------------

BIOS_CLEAR_SCREEN   = $00d0        ; uses r31
BIOS_DELAY          = $008f
BIOS_PUSH_K         = $0107        ; used to allow more subroutine stack space
BIOS_POP_K          = $011e
BIOS_DRAW_CHARACTER = $0679

;-------------------------------------------------------------------------------
; Colors

COLOR_RED           = $40
COLOR_BLUE          = $80
COLOR_GREEN         = $00
COLOR_BACKGROUND    = $C0

; Alternate (European) spellings...

COLOUR_RES          = COLOR_RED
COLOUR_BLUE         = COLOR_BLUE
COLOUR_GREEN        = COLOR_GREEN
COLOUR_BACKGROUND   = COLOR_BACKGROUND

;-------------------------------------------------------------------------------
; DEPRECATED equates.
; These present to be compatible with existing equate usage.  
; DO NOT USE THESE IN NEW CODE -- WE WANT TO GET RID OF THEM!

	IFCONST INCLUDE_DEPRECATED

clrscrn             = BIOS_CLEAR_SCREEN         ; DEPRECATED!
delay               = BIOS_DELAY                ; DEPRECATED!
pushk               = BIOS_PUSH_K               ; DEPRECATED!
popk                = BIOS_POP_K                ; DEPRECATED!
drawchar            = BIOS_DRAW_CHARACTER       ; DEPRECATED!

red                 = COLOR_RED                 ; DEPRECATED!
blue                = COLOR_BLUE                ; DEPRECATED
green               = COLOR_GREEN               ; DEPRECATED
bkg                 = COLOR_BACKGROUND          ; DEPRECATED

	ENDIF

;------------------------
; Schach RAM
;------------------------
ram		=	$2800					;location of RAM available in Schach cartridge

;===================================================================
; M A C R O S
;===================================================================

;-------------------------
; CARTRIDGE_START
; Original Author: Sean Riddle
; Inserts the $55 that signals a valid Channel F cartridge and an
; unused byte, which places the VES at the cartridge entry point, $802.

	MAC CARTRIDGE_START
	.byte	$55, $00					; valid cart indicator, unused byte
	ENDM

;-------------------------
; CARTRIDGE_INIT
; Original Author: Sean Riddle
; Initalizes the hardware and clears the complement flag.

	MAC CARTRIDGE_INIT
	; initalize the hardware
	lis	0
	outs	1
	outs	4
	outs	5
	outs	0

	; clear the complement flag (r32)
	lisu	4
	lisl	0
	lr	S, A
	ENDM

;-------------------------
; PROMPTS_NO_T
; Original Author: Sean Riddle
; This code functions the same as the "prompts" section of the BIOS,
; but this code doesn't have a "T?" prompt, so it's useful in games that
; don't have time limits or settings.

                MAC PROMPTS_NOT
prompts         SUBROUTINE
                LR   K,P                 ; 
                PI   pushk               ; 
.prompts2:      LI   $85                 ; red 5 (S)
                LR   $0,A                ; 
                PI   prompt              ; 
                LR   A,$4                ; 
                CI   $08                 ; is it button 4, Start?
                BF   $4,.notbut4         ; no, check others
.notbut2:
                PI   popk                ; yes, return
                PK                       ; 
                
.notbut4:       CI   $02                 ; is it button 2, Mode?
                BF   $4,.notbut2         ; 
                LI   $8e                 ; red M
                LR   $0,A                ; 
                PI   prompt              ; 
                LISU 3                   ; 
                LISL 6                   ; 
                LR   A,(IS)              ; 
                as      4                                       ;add the mode to the game #
                LR   (IS),A              ; 
                BF   $0,.prompts2        ; 
                ENDM
	
;-------------------------
; SETISAR
; Original Author: Blackbird
; Sets the ISAR to a register number, using lisu and lisl

	MAC SETISAR
	lisu	[[{1}] >> 3]
	lisl	[[{1}] & %111]
	ENDM
;-------------------------------------------------------------------------------
; The following required for back-compatibility with code which does not use
; segments.

            SEG

; EOF