Tandy 1000 Programmer's Reference Guide

Chapter 1 I System Calls
Macro Definitions for MS-DOS System Call
Examples
Interrupts
terminatemacro
int 20H
endm
;PROGRAM-TERMINATE
;interrupt20H
;ABS-DISK-READ
abs-disk-read macro
di5k,buffer,num-sectors,fir5t-5ector
mov a1,diskmov bx,offsetbuffer
mov cx,num-sectors
mov dx,fir5t_sector
int 25H ;interrupt25H
endm
POP
f
;ABS-DISK-WRITE
abs-di5k-write macro
disk,buffer,num-sectors,first-sector
mov a1,disk
mov cx,num_sector5
mov dx,first-sector
int 26H
endm
POPf
stay-resident macro last-instruc
mov dx,off5et last-instruc
inc dx
int 27H
endm
Functions
terminate-program macro
xor ah,ah
int 21
H
endm
read-kbd-and-echo macro
mov ah,
1
int 21 H
endm
display-char macrocharacter
mov d1,character
mov
ah,2
int 21 H
endm
;interrupt26GH
;STAY-RESIDENT
;interrupt27H
TERMINATE PROGRAM
function
EEH
READ-KED-AND-ECHO
function0lH
;DISPLAY-CHAR
;function E2H
137

Tandy 1000 Specifications

General

Processor	Intel 8088
Processor Speed	4.77 MHz
RAM	128 KB (expandable to 640 KB)
Operating System	MS-DOS 2.11
Manufacturer	Tandy Corporation
Release Year	1984
Storage	Single or double 5.25" floppy disk drive (360 KB), optional hard drive
Sound	Tandy 3-voice sound
Ports	Parallel, Serial
Graphics	CGA (Color Graphics Adapter)
Graphics Modes	320x200, 640x200