Refactor code and remove old files

LICENSE

@@ -336,4 +336,4 @@ This General Public License does not permit incorporating your program into
 proprietary programs.  If your program is a subroutine library, you may
 consider it more useful to permit linking proprietary applications with the
 library.  If this is what you want to do, use the GNU Lesser General
-Public License instead of this License.
+Public License instead of this License.

README.md

@@ -2,7 +2,7 @@
 
 by David Giller and Adrian Black
 
-See the YouTube video on [Adrian's Digital Basement](https://youtube.com/@adriansdigitalbasement) (direct video link pending release)
+See the YouTube video on [Adrian's Digital Basement](https://youtube.com/@adriansdigitalbasement) ([direct video link](https://youtu.be/KcrMssDp8Mo?si=5GnlTwxYQo68uhtq))
 
 ![Screenshot](img/screenshot.png)
 

dosbox-x.conf

@@ -0,0 +1,34 @@
+[sdl]
+	# output = surface
+	output = openglnb
+	display = 2
+
+[render]
+	# doublescan = true
+	aspect = true
+	scaler = normal2x forced
+	# scaler = hardware2x forced
+	# scaler = xbrz
+
+[dosbox]
+	startbanner = false
+	fastbioslogo = true
+	title = xtramtest
+	dpi aware = true
+
+	cputype = 8086
+	cycles = 240
+	enable pci bus = false
+	machine = cga
+	memsize = 0
+	memsizekb = 256
+	quit warning = false
+
+[dos]
+	lfn = true
+
+[autoexec]
+	@echo off
+	mount b .
+	b:
+	boot --bios b:xtramtest.8k

inc/init/010_cold_boot.inc → inc/010_cold_boot.inc

@@ -56,38 +56,3 @@ cold_boot:
 	mov	dx, 213h			; Expansion unit port
 	inc	ax				;   enable it
 	out	dx, al				;   do the enable
-	; mov	ax, 40h 			; Get BIOS data area segment
-	; mov	ds, ax				;   into ds register
-	; mov	si, [ds:72h]			; Save reset flag in si reg
-	; xor	ax, ax				;   cause memory check
-	; mov	bp, ax				;   will clobber the flag
-	; mov	bx, ax				; Start at segment 0000h
-	; mov	dx, 55AAh			;   get pattern
-	; cld					; Strings auto-increment
-
-
-	; 	cli			; disable IRQs
-
-	; 	mov	al, 1		; send a 1 to any POST card present to show we're running
-	; 	out	0x80, al
-
-	; .mask_nmi:
-	; 	xor	al, al		; mask NMIs using the NMI control port in case the MB didn't
-	; 	out	PORT_NMI_MASK, al
-
-	; .set_segregs:
-	; 	cld			; default direction is forward
-
-	; 	mov	ax, cs		; copy CS
-	; 	mov	ds, ax		; to DS
-	; 	mov	ss, ax		; and SS
-
-	; .init_8255P:	; Initialise the 8255 PPI chip.
-	; 	mov	al,99h
-	; 	out	PPI8255_ctrl, al	; Set port B to outputs, and ports A and C to inputs.
-
-	; 	mov	al,0F8h
-	; 	out	PPI8255_B,al		; 1. Reset/clear the two 'RAM parity error' latches.
-	; 					; 2. Turns off turbo mode if the clone XT motherboard supports 
-	; 					;    turbo control via bit 2.
-

inc/defines.inc

@@ -75,6 +75,8 @@ CGA_data	equ	3D5h		; 6845 Data Register
 CGA_ctrl	equ	3D8h		; Mode Control Register
 CGA_pal		equ	3D9h		; Color Select Register
 
+CGA_CTRL_VSVS	equ	0x08		; Vertical Sync bit
+
 FdcDor		equ	3F2h		; Digital Output Register (DOR)
 FdcMsr		equ	3F4h		; Main Status Register (MSR)
 FdcCdr0		equ	3F5h		; Command/Data Register 0