From: cuz Date: Sun, 24 Jul 2005 14:06:36 +0000 (+0000) Subject: Changes by Greg King X-Git-Tag: V2.12.0~300 X-Git-Url: https://git.sur5r.net/?a=commitdiff_plain;h=dcf2bf4976692afa32318b603f12873cdba4e3d1;p=cc65 Changes by Greg King git-svn-id: svn://svn.cc65.org/cc65/trunk@3543 b7a2c559-68d2-44c3-8de9-860c34a00d81 --- diff --git a/doc/intro.sgml b/doc/intro.sgml index 555958212..90905af0a 100644 --- a/doc/intro.sgml +++ b/doc/intro.sgml @@ -2,12 +2,14 @@
-cc65 compiler intro -<author>Ullrich von Bassewitz, <htmlurl url="mailto:uz@cc65.org" name="uz@cc65.org"> and CbmNut <htmlurl url="mailto:cbmnut@hushmail.com" name="cbmnut@hushmail.com"> -<date>07.13.2002 +<title>cc65 Compiler Intro +<author>Ullrich von Bassewitz, <htmlurl url="mailto:uz@cc65.org" name="uz@cc65.org">, +<and>CbmNut, <htmlurl url="mailto:cbmnut@hushmail.com" name="cbmnut@hushmail.com">, +<and><url name="Greg King" url="mailto:gngking@erols.com"> +<date>2005-7-22 <abstract> -How to use the cc65 C compiler - an introduction. +How to use the cc65 C language system -- an introduction. </abstract> <!-- Table of contents --> @@ -17,32 +19,32 @@ How to use the cc65 C compiler - an introduction. <sect>Overview<p> -This is a short intro of how to use the compiler and the binutils. It contains a -step-by-step example of how to build a complete application from one C and one -assembler module. This file does <em/not/ contain a complete reference for the -tools used in the process. There are separate files describing these tools in -detail. +This is a short intro of how to use the compiler and the bin-utils. It contains +a step-by-step example of how to build a complete application from one C and +one assembly modules. This file does <em/not/ contain a complete reference for +the tools used in the process. There are separate files describing those tools, +in detail (see <url url="index.html">). You are assumed to have downloaded and extracted the executables and the -target specific files. For example, for Windows users targeting C64, you need -cc65-win32-2.8.0.zip and cc65-c64-2.8.0.zip (or whatever the current cc65 -version is) extracted to the same directory. If you received the files as a -bzip2 archive (extension *.bz2), you will need to get the <htmlurl -url="http://sources.redhat.com/bzip2/#bzip2-latest" name="bzip2 package"> to -decompress it. +target-specific files. For example: for Windows users targeting C64, you need +<bf/cc65-win32-2.10.1.zip/ and <bf/cc65-c64-2.10.1.zip/ (or, whatever the +current cc65 version is) extracted to the same directory. If you received the +files as a bzip2 archive (extension <bf/.bz2/), you will need to get <url +url="http://sources.redhat.com/bzip2/#bzip2-latest" name="the bzip2 package"> +to decompress it. -<bf>Note</bf>: There is a much simpler way to compile this example using the -cl65 compiler and link utility. However, it makes sense to understand how the -separate steps work. How to do the example with the cl65 utility is described -<ref id="using-cl65" name="later">. +<bf/Note/: There is a much simpler way to compile this example, by using the +<bf/cl65/ compile-and-link utility. However, it makes sense to understand how +the separate steps work. How to do the example with the <bf/cl65/ utility is +described <ref id="using-cl65" name="later">. <sect1>Before we start<p> -You will find a copy of the sample modules used in the next section in the -samples/tutorial directory. Please check that the compiler and linker can -find the include library files by setting the environment variables -<tt/CC65_INC/ and <tt/CC65_LIB/ respectively. +You will find a copy of the sample modules, used in the next section, in the +"<tt>cc65/samples/tutorial</tt>" directory. Please make sure that the compiler +and linker can find the include and library files, by setting the environment +variables <tt/CC65_INC/ and <tt/CC65_LIB/, respectively. <sect1>The sample modules<p> @@ -50,24 +52,23 @@ find the include library files by setting the environment variables To explain the development flow, I will use the following example modules: hello.c: - <tscreen><code> - #include <stdio.h> - #include <stdlib.h> + #include <stdio.h> + #include <stdlib.h> - extern const char text[]; /* In text.s */ + extern const char text[]; /* In text.s */ - int main (void) - { - printf ("%s\n", text); - return EXIT_SUCCESS; - } + int main (void) + { + printf ("%s\n", text); + return EXIT_SUCCESS; + } </code></tscreen> text.s: <tscreen><code> - .export _text - _text: .asciiz "Hello world!" + .export _text + _text: .asciiz "Hello world!" </code></tscreen> @@ -80,34 +81,34 @@ is the C64. +---------+ | hello.c | +---------+ - | + | cc65 - \/ - +---------+ +---------+ + \/ + +---------+ +---------+ | hello.s | | text.s | - +---------+ +---------+ - | | + +---------+ +---------+ + | | ca65 ca65 \/ \/ - +---------+ +---------+ +----------+ +---------+ + +---------+ +---------+ +----------+ +---------+ | hello.o | | text.o | | c64.o | | c64.lib | - +---------+ +---------+ +----------+ +---------+ - | \ / | - | \ / | - | \ / | - +----------------------->ld65<-------------------------+ - \/ - hello + +---------+ +---------+ +----------+ +---------+ + | \ / | + | \ / | + | \ / | + +----------------------->ld65<-------------------------+ + \/ + hello </verb></tscreen> -<tt/c64.o/ (the startup code) and <tt/c64.lib/ (the c64 version of the runtime +<tt/c64.o/ (the startup code) and <tt/c64.lib/ (the C64 version of the runtime and C library) are provided in binary form in the cc65 package. <sect>The compiler<p> -The compiler translates one C source into one assembler source for each +The compiler translates one C source into one assembly source, for each invocation. It does <em/not/ create object files directly, and it is <em/not/ able to translate more than one file per run. @@ -115,7 +116,7 @@ In the example above, we would use the following command line, to translate <tt/hello.c/ into <tt/hello.s/: <tscreen><verb> - cc65 -O -I ../include -t c64 hello.c + cc65 -O -I ../../include -t c64 hello.c </verb></tscreen> The <tt/-O/ switch tells the compiler to do an additional optimizer run, which @@ -124,155 +125,167 @@ about the size, but want to have slightly faster code, use <tt/-Oi/ to inline some runtime functions. The <tt/-I/ switch gives a search path for the include files. You may also set -the environment variable CC65_INC to the search path. +the environment variable <tt/CC65_INC/ to the search path. -The <tt/-t/ switch is followed by the target system. +The <tt/-t/ switch is followed by the target system name. -If the compiler does not complain about errors in our hello world, we will -have a file named "<tt/hello.s/" in our directory that contains the assembler -source for the hello module. +If the compiler does not complain about errors in our "hello world" program, we +will have a file named "<tt/hello.s/", in our directory, that contains the +assembly source for the <bf/hello/ module. -For more information about the compiler see <htmlurl url="cc65.html" -name="cc65.html">. +For more information about the compiler, see <url url="cc65.html">. <sect>The assembler<p> -The assembler translates one assembler source into an object file for each -invocation. The assembler is <tt/not/ able to translate more than one source +The assembler translates one assembly source into an object file, for each +invocation. The assembler is <em/not/ able to translate more than one source file per run. -Let's translate the hello.s and text.s files from our example: +Let's translate the "hello.s" and "text.s" files from our example: <tscreen><verb> - ca65 hello.s - ca65 -t c64 text.s + ca65 hello.s + ca65 -t c64 text.s </verb></tscreen> The <tt/-t/ switch is needed when translating the <tt/text.s/ file, so the -text is converted from the input character set (usually ISO-8859-1) into the -target character set (PETSCII) by the assembler. The compiler generated file -<tt/hello.s/ does not contain any character constants, so specification of a -target is not necessary (it wouldn't do any harm, however). +text is converted from the input character-set (usually ISO-8859-1) into the +target character-set (PETSCII, in this example) by the assembler. The +compiler-generated file <tt/hello.s/ does not contain any character constants, +so specification of a target is not necessary (it wouldn't do any harm, +however). If the assembler does not complain, we should now have two object files (named <tt/hello.o/ and <tt/text.o/) in the current directory. -For more information about the assembler see <htmlurl url="ca65.html" -name="ca65.html">. +For more information about the assembler, see <url url="ca65.html">. <sect>The linker<p> -The linker combines several object and library file into one output file. ld65 -is very configurable, but fortunately has a builtin configuration for the C64, -so we don't need to mess with configuration files here. +The linker combines several object and library files into one output file. +<bf/ld65/ is very configurable, but fortunately has a built-in configuration +for the C64, so we don't need to mess with configuration files, here. The compiler uses small functions to do things that cannot be done inline -without big impact on code size. These runtime functions, together with the C -library are in an object file archive named after the system, in this case -"<tt/c64.lib/". We have to specify this file on the command line so that the -linker can resolve these functions. +without a big impact on code size. Those runtime functions, together with the +C library, are in an object-file archive named after the system, in this case, +"<tt/c64.lib/". We have to specify that file on the command line, so that the +linker can resolve those functions. -A second file (this time an object file) needed, is the startup code that +A second file (this time, an object file) needed is the startup code that prepares the grounds for the C program to run. The startup file must be executed first, so it must be the first file on the linker command line. Let's link our files to get the final executable: <tscreen><verb> - ld65 -t c64 -o hello c64.o hello.o text.o c64.lib + ld65 -t c64 -o hello c64.o hello.o text.o c64.lib </verb></tscreen> The argument after <tt/-o/ specifies the name of the output file, the argument after <tt/-t/ gives the target system. As discussed, the startup file must be -the first file on the command line (you may have to add a path here, if +the first input file on the command line (you may have to add a path here, if <tt/c64.o/ is not in your current directory). Since the library resolves -imports in <tt/hello.o/ and <tt/text.o/, it must be specified <em/after/ these +imports in <tt/hello.o/ and <tt/text.o/, it must be specified <em/after/ those files. After a successful linker run, we have a file named "<tt/hello/", ready for our C64! -For more information about the linker see <htmlurl url="ld65.html" -name="ld65.html">. +For more information about the linker, see <url url="ld65.html">. <sect>The easy way (using the cl65 utility)<label id="using-cl65"><p> -The cl65 utility is able to do all of the steps described above in just one -call, and it has defaults for some options that are very well suited for our -example. +The <bf/cl65/ utility is able to do all of the steps described above, in just +one command line, and it has defaults for some options that are very +well-suited for our example. -To compile both files into one executable enter +To compile both files into one executable, enter: <tscreen><verb> - cl65 -O -I ../include hello.c text.s + cl65 -O -I ../../include -L ../../lib hello.c text.s </verb></tscreen> -(The <tt/-I/ switch is not needed if you are working under Linux with the -include files in the default path, or the <tt/CC65_INC/ environment variable -is set correctly). - -The cl65 utility knows, how to translate C files into object files (it will -call the compiler and then the assembler). It does also know how to create -object files from assembler files (it will call the assembler for that). It -knows how to build an executable (it will pass all object files to the -linker). And, finally, it has the C64 as a default target and will supply the +(The <tt/-I/ option is not needed if you are working under a Unix-like system +with the include files in their default path, or if the <tt/CC65_INC/ +environment variable is set correctly. The <tt/-L/ option is not needed if the +libraries are in their default path, or if the <tt/CC65_LIB/ environment +variable is set correctly. [Those two environment variables should be set to +absolute paths.]) + +The <bf/cl65/ utility knows how to translate C files into object files (it will +call the compiler, and then, the assembler). It does know also how to create +object files from assembly files (it will call only the assembler, for that). +It knows how to build an executable (it will pass all object files to the +linker). And finally, it has the C64 as a default target, and will supply the correct startup file and runtime library names to the linker, so you don't have to care about that. The one-liner above should give you a C64 executable named "<tt/hello/" in the current directory. -For more information about the compile & link utility see <htmlurl -url="cl65.html" name="cl65.html">. +For more information about the compile & link utility, see <url +url="cl65.html">. + + <sect>Running The Executable<p> -<bf>Note: this section is incomplete!</bf> +<em/Note: this section is incomplete!/ -Depending on the target, the compiler chooses several methods of making a -program available for execution. Here we list sample emulators and +Depending on the target, cc65 chooses several methods of making a +program available for execution. Here, we list sample emulators and instructions for running the program. Unless noted, similar instructions would also apply to a real machine. One word of advice: we suggest you clear the screen at the start, and wait for a keypress at the end of your program, as each target varies in it's start and exit conditions. -<sect1>Apple<p> -<bf>AppleWin 1.10.4</bf> (available at -<url url="http://www.jantzer-schmidt.de/applewin/">): Emulates Apple II+/IIe -computer, with sound, video, joysticks, serial port, and disk images. Roms and -dos disk included. Includes monitor. Only for Windows. The package comes with -roms and dos3.3 disk (called master.dsk), however you will need a2tools -(available at <url url="http://hotel04.ausys.se/pausch/apple2/#a2tools">). +<sect1>Apple + +<sect2>AppleWin 1.10.4<p> +Available at <url url="http://www.jantzer-schmidt.de/applewin/">: + +Emulates Apple II+/IIe computers, with sound, video, joysticks, serial port, +and disk images. Includes monitor. Only for Windows. The package comes with +ROM and DOS 3.3 disk (called "master.dsk") images; however, you will need +<bf/a2tools/ (available at <url +url="http://hotel04.ausys.se/pausch/apple2/#a2tools">). Compile the tutorial with <tscreen><verb> cl65 -O -t apple2 hello.c text.s </verb></tscreen> +for the Apple II, or: +<tscreen><verb> +cl65 -O -t apple2enh hello.c text.s +</verb></tscreen> +for the Apple IIe. -Then insert the file into an Apple disk image for use with an emulator. Copy -the master.dsk which comes with Applewin and rename it to cc65.dsk, then use -a2tools: +Then, insert the file into an Apple disk image, for use with an emulator. Copy +the <tt/master.dsk/ which comes with <bf/Applewin/, and rename it to +<tt/cc65.dsk/, then use <bf/a2tools/: <tscreen><verb> a2tools in -r b cc65.dsk TEST hello </verb></tscreen> -Note that a convention in the Apple world is that hello is the file which is -automatically run upon booting a DOS disk, sort of like the Autoexec.bat of -the PC world. We've avoided this in the example however. Also, the TEST -parameter must be in caps, and is the name of the program as it will appear on -the Apple disk. +Note that a convention in the Apple world is that "hello" is the file which is +run automatically upon booting a DOS disk, sort of like the "autoexec.bat" of +the MSDOS/Windows world. We've avoided that in the example, however. Also, +the <tt/TEST/ parameter must be in caps., and is the name of the program as it +will appear on the Apple disk. -Start the emulator, click on the Disk 1 icon, and point to cc65.dsk, then -click the big Apple logo to boot the system. Then type this on the Apple: +Start the emulator, click on the <bf/Disk 1/ icon, and point to <bf/cc65.dsk/; +then, click the big Apple logo, to boot the system. Then, type this on the +Apple: <tscreen><verb> BRUN TEST @@ -282,14 +295,17 @@ You will see the "Hello, World!" appear on the same line. Thanks to Oliver Schmidt, <htmlurl url="mailto:oliver@jantzer-schmidt.de" name="oliver@jantzer-schmidt.de"> for his help in completing this section. -<sect1>Atari<p> -<bf>Atari800Win Plus 3.0</bf> (available at -<url url="http://www.a800win.atari-area.prv.pl">): Emulates Atari -400/800/65XE/130XE/800XL/1200XL/5200, with stereo sound, disk images, scanline -exact NTSC/PAL video, joysticks, mouse, cartridges and ram expansions. -Includes monitor. Unfortunately only for Windows. You will need the emulator, -atarixl.rom or atariosb.rom/ataribas.rom and dos25.xfd files (not supplied). +<sect1>Atari + +<sect2>Atari800Win Plus 3.0<p> +Available at <url url="http://www.a800win.atari-area.prv.pl">: + +Emulates Atari 400/800/65XE/130XE/800XL/1200XL/5200, with stereo sound, disk +images, scanline-exact NTSC/PAL video, joysticks, mouse, cartridges, and RAM +expansions. Includes monitor. Unfortunately, only for Windows. You will need +the emulator, "atarixl.rom" or "atariosb.rom"/"ataribas.rom", and "dos25.xfd" +files (not supplied). Compile the tutorial with @@ -297,43 +313,74 @@ Compile the tutorial with cl65 -O -t atari hello.c text.s </verb></tscreen> -Start the emulator, choose File>Autoboot image or File>Load executable, and -point to the hello executable. It is customary to rename executables of this -type to hello.xex. The file has a 7 byte header meant to be loaded directly -from Atari DOS 2/2.5 or compatibles. +Start the emulator, choose <bf/File>Autoboot image/ or <bf/File>Load +executable/, and point to the "<bf/hello/" executable. It is customary to +rename executables of that type to "<bf/hello.xex/". The file has a 7-byte +header meant to be loaded directly from Atari DOS 2/2.5 or compatibles. -On a real Atari, you would need a disk drive and Atari Dos 2.5 or compatible. +On a real Atari, you would need a disk drive, and Atari DOS 2.5 or compatible. Turn on the computer, type <tscreen><verb> DOS </verb></tscreen> -at the basic prompt, then choose N. CREATE MEM.SAV then choose L. BINARY LOAD -and enter HELLO. +at the BASIC prompt, then choose <bf/N. CREATE MEM.SAV/, +then choose <bf/L. BINARY LOAD/, and enter <tt/HELLO/. -The emulation also supports this method. Look at Atari>Settings and check -Enable H: Patch for Hard Disk Devices, then Atari>Hard disks and set the path -of H1: to your executables directory, then use H0:HELLO.XEX in the above -procedure (after pressing L) to access your hardrive directly. +The emulation, also, supports that method. Look at <bf/Atari>Settings/, and +check <bf/Enable H: Patch for Hard Disk Devices/, then <bf/Atari>Hard +disks/, and set the path of <bf/H1:/ to your executables directory, then use +"<bf/H0:HELLO.XEX/" in the above procedure (after pressing <tt/L/), to access +your harddrive directly. -<bf>Note:</bf> There is no delay after the program exits, as you are returned +<bf/Note/: There is no delay after the program exits, as you are returned to the DOS menu. Your C program should wait for a keypress if you want to see any output. -<sect1>Commodore<p> -<bf>Vice 1.15</bf> (available at -<url url="ftp://ftp.funet.fi/pub/cbm/crossplatform/emulators/VICE/">): -Emulates Commodore 64/128/Vic 20/PET/CBM II computers. Missing is the Plus/4 -and Commodore 16. Supports printer, serial port, stereo sound, disk drives and -images, ram expansions, cartridges, cycle exact NTSC/PAL video, mice, -joysticks. Includes monitor. Runs on Win9x/NT/2000/XP/ME/OS2/MSDOS, Beos x86, -Acorn RISC OS, and many Unixes. +<sect1>Commodore -Start the desired version of the emulator, choose File>Autoboot disk/tape -image, and choose your executable. The file has a 14 byte header which -corresponds to a PRG format BASIC program, consisting of a single line; +<sect2>VICE 1.16<p> +Available at <url +url="http://www.zimmers.net/anonftp/pub/cbm/crossplatform/emulators/VICE/">, +<newline>and at <url +url="http://www.ibiblio.org/pub/micro/commodore/crossplatform/emulators/VICE/">: + +Emulates Commodore 64/128/VIC-20/PET/CBM II/Plus 4 computers. Supports +printers, serial port and adapters, stereo sound, disk drives and images, RAM +expansions, cartridges, ethernet connection, cycle-exact NTSC/PAL video, mice, +and joysticks. Includes monitor. Runs on MSDOS/PCDOS, Win9x/ME/NT/2000/XP, OS2, +BeOS x86, Acorn RISC OS, and most Unixes. + +Compile the tutorial with +<tscreen><verb> +cl65 -O -t <sys> hello.c text.s +</verb></tscreen> +Substitute the name of a Commodore computer for that <tt/<sys>/: +<itemize> +<item><tt/c128/ +<item><tt/c16/ +<item><tt/c64/ +<item><tt/cbm510/ +<item><tt/cbm610/ +<item><tt/pet/ +<item><tt/plus4/ +<item><tt/vic20/ +</itemize> + +Start the desired version of the emulator (CBM510 and CBM610 programs run on +the CBM II [<tt/xcbm2/] emulator). + +In the Windows versions of VICE, choose <bf>File>Autoboot disk/tape +image...</bf>, choose your executable, and click <bf/OK/. + +In the Unix versions, hold down the mouse's first button. Move the pointer to +<bf>Smart-attach disk/tape...</bf>, and release the button. Choose your +executable, and click <bf/Autostart/. + +The file has a 14-byte header which corresponds to a PRG-format BASIC program, +consisting of a single line, similar to this: <tscreen><code> 1000 sys2061 @@ -342,30 +389,113 @@ corresponds to a PRG format BASIC program, consisting of a single line; On a real Commodore with attached disk drive, you would type: <tscreen><verb> -LOAD "HELLO",8 +LOAD "0:HELLO",8 </verb></tscreen> -for Vic 20/C64, or +for VIC-20/C64, or: <tscreen><verb> -DLOAD "0:HELLO" +DLOAD "HELLO" </verb></tscreen> -on PET/CBM II/C128, then type +on PET/CBM II/C128/C16/Plus 4; then, type <tscreen><verb> RUN </verb></tscreen> +On a Commodore 128, you can combine those two commands: +<tscreen><verb> +RUN "HELLO" +</verb></tscreen> + The output will appear on a separate line, and you will be returned to a BASIC prompt. + +<sect1>GEOS<p> +Available at <it/Click Here Software's/ <url +url="http://cmdrkey.com/cbm/geos/geos1.html" name="GEOS download page">: + +<it><bf/G/raphics <bf/E/nvironment <bf/O/perating <bf/S/ystem.</it> +It provides a WIMP GUI (Windows, Icons, and Mouse-Pointer Graphical User +Interface) for Commodore's computer models <bf/64/ and <bf/128/. It can be +controlled by many different types of input devices: +<itemize> +<item>keyboard +<item>joysticks +<item>mice +<item>trackballs +<item>graphics drawing tablets +<item>light-pens +</itemize> + +The tutorial files are different for GEOS. You will find them "next door," in +"<tt>cc65/samples/geos</tt>"; they are called "<tt/hello1.c/" and +"<tt/apphello1.grc/". + +Compile the tutorial with +<tscreen><verb> +cl65 -O -t geos hello1.c apphello1.grc +</verb></tscreen> +Copy the resulting file "<tt/hello1/" onto a (GEOS-format) disk. + +Boot the GEOS master disk/image. + +<quote> +When you want to run GEOS in an emulator, you must adjust that emulator so that +it does a "true drive" emulation. Each emulator has its own way of turning that +feature on. +</quote> + +<quote> +VICE even has different ways that depend on which operating system is running +the emulator. +<itemize> +<item>In Windows, you must click on <bf/Options/ (in an always visible menu). + Then, you must click on <bf/True drive emulation/. +<item>In Unix, you must <em/hold down/ the second button on your mouse. Move + the pointer down to <bf/Drive settings/. Then, move the pointer over to + <bf/Enable true drive emulation/. (If there is a check-mark in front of + those words, that feature already is turned on -- then, move the pointer + off of that menu.) Release the mouse button. +</itemize> +</quote> + +Find the <bf/CONVERT/ program on the boot disk [tap the 6-key; then, you +should see it's icon in the fourth position on the <bf/deskTop/'s directory +notePad]. Move GEOS's pointer over to <bf/CONVERT/'s icon; double-click +it to run that program. Click on the <bf/Disk/ icon; put the disk with +"<tt/hello1/" into the drive; and, click the <bf/OK/ icon. Use the little +icons under the list of file-names to move through that list until you find +"<tt/hello1/". Click on it; and then, click on the <bf/Convrt/ icon. +<bf/CONVERT/ will ask you to confirm that you choose the correct file; click +<bf/YES/ if you did (or, click <bf/NO/ if you made a mistake). After the +program has converted "<tt/hello1/" from a CBM file into a GEOS file, it will +announce what it did -- click on <bf/OK/. <bf/CONVERT/ will show the file list +again. This time, click on <bf/Quit/. + +(You might need to put the boot disk back into the drive, in order to reload +<bf/deskTop/. Then, you must swap back to the disk with the tutorial program +on it, and click on its disk icon [on the right side of the screen].) + +Now, you must find <bf/hello1/. Click on the lower left-hand corner of the +directory notePad. Look at the eight file-positions on each page until you see +<bf/hello1/. Double-click on its icon. + +The output is shown in a GEOS dialog box; click <bf/OK/ when you have finished +reading it. + + +<sect1>Contributions wanted<p> + We need your help! Recommended emulators and instructions for other targets -are missing. We suggest an emulator with good compatibility. Also, being able -to run all computers in the target series is good for target compatibility -testing. A machine language monitor is almost essential for debugging, but a -native debugger could be used as well. +are missing. We suggest that you choose emulators with good compatibility. +Also, being able to run all computers in the target series is good for +target compatibility testing. A machine-language monitor is almost essential +for debugging, but a native debugger could be used, as well. -Finally, emulators which run on Unix/Windows would help reach a wider audience. +Finally, emulators which run on Unix or Windows would help to reach a wider +audience. </article>