Apple IIgs Firmware Reference Manual (Rob Peck) - Brutal Deluxe

196 Pages·2010·6.19 MB·English

Apple IIGS Firmware
Reference Manual
Beta Draft
10/24/86
Writer: Rob Peck
Apple Technical Publications
This document containspreliminaryinformation. It does notinclude
•finaleditorialcorrections
•jinalartwork
•anindex
Itmay notincludefinal technicalchanges
_()Dvri~ht ©1986 ADDle ComDuter, Inc.
/
l; APPLE COMPUTER, INC.
7his manual is copyrighted by
",pple or by Apple's suppliers,
''lith all rights reserved. Under
the copyright laws, this manual
may not be copied, in whole or
in part, without the written
consent of Apple Computer,
Inc. This exception does not
allow copies to be made for
others, whether or not sold, but
all of the material purchased
may be sold, given, or lent to
another person. Under the law,
copying includes translating
~nto another language.
s;: Apple Computer, Inc., 1986
20525 Mariani Avenue
Cupertino, California 95014
(',v8) 996-1010
"?ple and the Apple logo are
""'sistered trademarks of Apple
":.mputer, Inc.
_ditional credit lines as
",ded]
~ultaneously published in the
.ted States and Canada.
Table o!Contents
CONTENTS
Chapter 1. Apple fiGS Firmware Overview
Introduction
A wordaboutotherApple llGS finnware
Therole offinnware in theApplellGS system
Apple llGS finnware overview
Chapter 2. Notes for Programmers
Introduction
ApplellGS finnware routines
Othergeneral topics
Chapter 3. System Monitor Firmware
Introduction
Invoking the Monitor
Monitorcommand syntax
Monitorcommandtypes
Monitormemory commands
Registers and flags
MiscellaneousMonitorcommands
Special tricks with the Monitor
Machine-languageprograms
TheMini-Assembler
Summary ofMonitorinstructions
Chapter 4. Video Firmware
Introduction
StandardI/Olinks
Standard inputroutines
Standard outputroutines
Otherfinnware I/O routines
The text window
Chapter 5. Serial Port Firmware
Introduction
Compatability
Operatingmodes
Handshaking
Operating commands
Programming with Serial Portfinnware
Error handling
Buffering
Interruptnotification
Backgroundprinting
Rechargeroutine
Extendedinterface
Chapter 6. Disk II Support
Introduction
Startup
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Table ofContents
Slot5 boot
Apple 3.5 drive
, I
Chapter 7. SmartPort Firmware
Introduction
Using SmartPort
LocatingSmartPort
Locating thedispatch address
SmartPortcallparameters
SmartPortassignmentofunitnumbers
Issuing acall to SmartPort
DevicespecificSmartPortcalls
ROMDiskdriver
Summary ofSmartPorterrorcodes
The SmartPortbus
Chapter 8. Interrupt Handler
Introduction
Whatis aninterrupt?
The built-in InteruptHandler
Summary ofsysteminterrupts
Environmenthandling for interruptprocessing
Handling Breakinstructions
Applenos Mouseinterrupts
Serialportinterruptnotification
ChapterSummary
Chapter 9. Apple Desktop Bus Microcontroller
Introduction
ADB microcontrollercommands
Microcontroller statusbyte
Chapter 10. Mouse Firmware
Introduction
Mouse position data
Using the Mouse fumware
Summary offumware calls
Pascalcalls
Assembly-languagecalls
Appendix A. Roadmap to the Apple IIGS Technical Manuals
Appendix B. Firmware ill Bytes
Appendix C. Firmware Entry Points in Bank 00
Appendix D. Vectors
Appendix E. Soft Switches
Appendix F. Disassembler/Mini-Assembler Opcodes
Appendix G. The Control Panel
BetaDrajt T.O.C.-2 10/24/86
Table o/Contents
Appendix H. Banks $EO/$El
""'letaDrajt T.o.C.-3 10/24/86
• APPLE COMPUTER, INC.
This manual is copyrighted by
Apple or by Apple's suppliers,
with all rights reserved. Under
the copyright laws, this manual
may not be copied, in whole or
inpart, without thewritten
consent of Apple Computer,
Inc. This exception does not
allow copies to be made for
others, whether or notsold, but
all ofthe material purchased
may be sold, given, or lent to
another person. Under the law,
copying includes translating
into another language.
e Apple Computer, Inc., 1986
20525 Mariani Avenue
Cupertino, California 95014
[phone]
Apple and the Apple logo are
registered trademarks of Apple
Computer, Inc.
[additional credit lines as
needed]
Simultaneously published in the
United States and Canada.
(
Firmware Overview
Chapter 1
Apple IIGS Firmware Overview
This chapter gives a briefoverview ofthe ApplellGS firmware and how itrelates to the rest
ofthe sytem software.
Introduction
The ApplellGS firmware is composed ofvarious kinds ofroutines that are storedin the
system'sread-only memory (ROM). The Apple llGS ftrmware routines provide the means
to adapt andcontrol the ApplellGS system.
Thefollowing is a listofthe AppleIIGS firmware routines thatare coveredin this manual:
• SystemMonitorfIrmware
• Video fIrmware (I/O routines)
• SerialPortfIrmware (forcharacter-at-a-timeI/O)
• Disk Support firmware (slot 6 support)
• SmartPort ftrmware (for blockdevice I/O)
• InterruptHandler
• Apple Desktop Bus microcontroller
• Mouse fIrmware
A word about other Apple IIGS firmware
The above topics do not comprise the whole body ofApplellGS ftrmware. The Apple IIGS
ROM contains other fmnware, importantenough to warrant separate manuals: the Apple
IIGS Tools (described in detail in theAppleIIGS Tools ReferenceManual), Applesoft
BASIC (describedin the ApplesoftBASIC Reference Manual), and AppleTalk (described
in theAppleTalkManual).
Apple IIGSTools
TheAppleIIGS Tools provide a means ofconstructing application programs thatconform
to the standarduserinterface. By offering a common setofroutines thatevery application
can call to implementthe userinterface, the tools not onlyensurefamiliarity and
consistency for the user, but also help toreduce the application's code size and
development time.
AppleTalk
AppleTalkis a local-areanetwork thatprovides communication andresource sharing with
up to 32 computers, disks, printers, IIlOdems, and otherperipherals. AppleTalk consists of
communications hardware and a set ofcommunications protocols. This hardware/software
BetaDraft 1-1 10/24/86
Firmware Overview
package, together with the computers, cables andconnectors, sharedresource managers
(servers), and specialized applications software, functions in three major configurations:
small-area interconnect systems, a tributary to alargernetwork, and aperipheral bus
between Applecomputers and theirdedicatedperipheral devices.
The role of firmware in the Apple IIGS system
The firmware is an interfaceto the system's hardware thatcontrols thedisplay, the mouse,
serial I/O, and disk drives. Moreover, fmnware programs, such as the Monitor and
ControlPanel, workdirectly with the systemmemory.
Traditionally, programmers havecontrolled hardwaredirectly through theirapplication
programs, bypassing any systemfmnware. The disadvantageofthis approach is that the
programmerhas to do alot more work. Butmoreimportantthan thatis the increasing
likelihood thattheresulting programwill beincompatible eitherwith otherprograms or
with future versions ofthe computer. By using the fmnware interfaces as defined, a
programmercanmaintain compatibilitywith this andfuture releases ofthe system.
Levels of program operation
You can think ofthe differentlevels ofprogramoperation on the Apple IIGS as a heirarchy,
with ahardware layerat the bottom, firmware layers in the middle, and the application at
the top. Figure 1-1 shows ahierarchy ofcommandlevels-generally speaking, higher
level components calIonlower-level ones. (The levels are separated by the lines, and the
hardware components have heavy outlines.)
I I
Application
I
I ProDOS I Loader
I
(
Monitor I I Finnware I I Drivers I I Toolbox
I I I I I
CPU I Memory I Keyboard Display I Slots
Figure 1·1. Levels ofprogram operation
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Firmware Overviel'>'
Apple IIGS firmware overview
The following paragraphs provide an overviewofthe Apple ITGS firmware described in
this manual.
System Monitor firmware
The SystemMonitorfmnware is a setofroutines that you can use tooperate thecomputer
at the machine-languagelevel. You can examine andchangememory locations, examine
and changeregisters, call systemroutines, and assemble anddisassemble machine
language programs using the SystemMonitorfmnware.
Video firmware
Video fmnware allows you to manipulate the screen, in low resolution mode andtext
mode, through your application programs and from the keyboard. Communication
between the keyboard and the video screen is controlled by fmnware subroutines, escape
codes, and control characters. The Video fmnware provides on-screen editing, keyboard
input, output to the screen, and cursorcontrol.
Serial Port firmware
The Apple ITGS Serial Portfmnware facilitates serial communication with external devices,
such as printers and modems. The serial fmnware provides supportfor such things as
optional hardware and/or software handshaking, and backgroundprinting. There are two
serial pons, either ofwhich can be configured as aprinteror amodem port.
Disk Support firmware
The AppleITGS DiskIT fmnware is a disk-support subsystem. It uses a built-in Integrated
Woz Machine (IWM) chip and accommodates DiskIT (DuodiskorUnidisk) drives. Slot 6
is the standard Disk II support slot.
SmartPort firmware
DiskITdevices are directly manipulated by slot 6control hardware. Intelligent devices, by
contrast, are not directly manipulated by hardware, butratherare controlled by software
driven command streams. Such devices arelabeledas intelligentdevices because they have
theirown controller that understands how to interpretthesecommand streams. The
SmartPort fmnware is a setofassembly-languageroutines thatpermityou to attach a series
ofintelligentdevices to the external diskportofthe Apple ITGS system. Using the
SmartPortfmnware, you can control these devices through SmartPort calls, such as Open,
Close, Format, Read Block, and Write Block.
Interrupt Handler
System interrupts halt the execution ofaprogram ortheperformance ofafunction or
feature. The system contains a built-in interrupt handler, a user's interrup't-handlerentry
point, and ameans to notify the user when an interrupt occurs.
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Firmware Overview
Apple Desktop Bus (ADB) microcontroller
I
The ADB Microcontrolleris used toreceive information fromperipheral units attachedto
the Apple Desktop Bus (ADB). TheADB microcontrollerpolls the internal keyboard,
sensing key-up andkey-down events as well as controlkeys andoptionally buffers them
for later access by the 65816. In addition, the ADB uC acts as hostfor the ADB
peripherals, such as the detachable keyboard and mouse. The ADB Microcontrollerhas its
own built-in setofinstructions, including Talk, Listen, SendReset, and Rush.
Mouse firmware
TheApple nOS Mouse frrmware supplies thecommunicationprotocol for sensing the
current status ofthe mouse. The Mousefmnware tracks mousepositiondata and mouse
button status, and provides entry points for assembly-languagecontrol.
Diagnostic routines
The systemdiagnostics contain manufacturing testroutines. Noexternal entry points are
definedfor the systemdiagnostics at this time. Thus the diagnostics are notdocumentedin
this manual.
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