Difference between revisions of "Ves.h"

Revision as of 13:53, 17 November 2012

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:

;====================================================================
; VES.H
; Fairchild Channel F Header File
; 20041030
; by Kevin Lipe
;====================================================================

VESH_VERSION = 101

; THIS IS A PRELIMINARY RELEASE OF *THE* "STANDARD" VES.H
;
; This file defines memory mapping and BIOS calls for the
; Fairchild Channel F, and also standardized Macros. 

;====================================================================
; E Q U A T E S
;====================================================================

;------------------------
; BIOS Calls
;------------------------
clrscrn         =       $00d0                                   ;uses r31
delay           =       $008f
pushk           =       $0107                                   ;used to allow more subroutine stack space
popk            =       $011e
drawchar        =       $0679

;------------------------
; Colors
;------------------------
red             =       $40
blue            =       $80
green           =       $00
bkg             =       $C0
clear		    =	    $FF

;------------------------
; 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