EasyManuals Logo

Tandy 1000 Programmer's Reference Guide

Default Icon
251 pages
To Next Page IconTo Next Page
To Next Page IconTo Next Page
To Previous Page IconTo Previous Page
To Previous Page IconTo Previous Page
Page #188 background imageLoading...
Page #188 background image
ChaQter
5
I
Device Drivers
NON-DESTRUCTIVE READ NO WAIT
Commandcode
=
5
ES:BX
13-BYTE
Request Header
BYTE Read from device
If the character device returns busy bit
=
0 (characters in
buffer), then the next character that would be read is returned.
This character is not removed from the input buffer (hence the
term non-destructive read). This call allows
MS-DOS
to
look
ahead one input character.
STATUS
Command codes
=
6
and 10
ES:BX
13-BYTE Request Header
All the driver must do is set the status word and the busy bit.
FLUSH
Command codes
=
7
and
11
ES:BX
13-BYTE Request Header
The FLUSH call tells the driver
to
flush (terminate) all pending
requests. This call is used
to
flush the input queue on character
devices.
186

Other manuals for Tandy 1000

Questions and Answers:

Question and Answer IconNeed help?

Do you have a question about the Tandy 1000 and is the answer not in the manual?

Tandy 1000 Specifications

General IconGeneral
ProcessorIntel 8088
Processor Speed4.77 MHz
RAM128 KB (expandable to 640 KB)
Operating SystemMS-DOS 2.11
ManufacturerTandy Corporation
Release Year1984
StorageSingle or double 5.25" floppy disk drive (360 KB), optional hard drive
SoundTandy 3-voice sound
PortsParallel, Serial
GraphicsCGA (Color Graphics Adapter)
Graphics Modes320x200, 640x200

Related product manuals