	title	'Inhibit Video Blanking on 84 TurboROM'


;**********************************************************
;
;	Assemble it using ASM which is supplied with
;	your CP/M system.
;
;	"ASM NOBLANK<CR>"
;
;(this takes the file NOBLANK.ASM and generates a file NOBLANK.HEX)
;
;	Generate a COM file with LOAD which was also supplied with
;	your CP/M system.
;
;	"LOAD NOBLANK<CR>"
;
;(this takes the file NOBLANK.HEX and generates a file NOBLANK.COM)
;
;	You can now run NOBLANK
;********************************************************************

CLRSCR		equ	01AH		;clear Kaypro screen
CR		equ	00DH		;carriage return
LF		equ	00AH		;line feed
PRINT$STR	equ	9		;CP/M string printer
BDOS		equ	0005		;standard BDOS entry point
WBOOT		equ	0000		;standard Warm Boot Entry 
HRDPTR		equ	0ffech		;pointer to high memory tables	


	ORG	100H		;standard runtime address
	jmp	start		;skip around messages

sign$on:
	db	CLRSCR
	db	'NOBLANK  Copyright (c) 1986 Advent Products, Inc.'
	db	CR,LF,'$'
	
	ds	16
stack	equ	$


start:	lxi	sp,stack	;set up our own stack
	lxi	d,sign$on
	mvi	c,PRINT$STR
	call	BDOS
;
;	disable video blanking by setting DISBLK flag to non-zero
;
	lhld	HRDPTR		;get pointer to high memory tables 
	lxi	d,0020h		;offset to DISBLK flag
	dad	d
	mvi	m,0ffh		; disable blanking

	jmp	WBOOT		; exit this code

	end
