Enterprise Emulator

Beginners would mostly like to try out programs downloaded from the net. The easiest way to do this is to emulate an Enterprise computer with a cassette tape recorder.

Emulation of a machine with a cassette tape recorder
In the early days of the Enterprise, programs could only be loaded into the Enterprise using a tape recorder; the floppy disk and hard drive capabilities appeared later. When emulating a machine with cassette tape recorder, the EP32 actually reads files from the hard drive of the PC. To emulate a machine with cassette tape recorder you have to do the following:

When emulating a machine with cassette tape recorder, it is unfortunately not possible to save files. So do not write programs within this type of emulation, because you will not be able to save them! Furthermore you can not use tape recorder emulation for programs which run only on a machine with floppy drive (there are only a few programs like that). If you want to save a program (e.g. a basic program) using the EP32 emulator, you must emulate a machine with floppy disk drive.

Emulation of a machine with a floppy drive
You have to have a floppy drive in your PC, even though this device is becoming more and more out-of-fashion. To emulate an Enterprise machine with a floppy drive you must do the following:

When emulating a machine with floppy drive, you must first copy the files of the desired program to the floppy disk, of course. It's essential that before starting emulation of a machine with floppy drive, you must close all Windows programs that may use the floppy drive. Even in Explorer the contents of the floppy drive should not be displayed. Run the emulator only after closing all such Windows programs! Otherwise the emulator won't read the floppy at all.
You can save files with this type of emulation, and they will appear on the floppy disk. If you want to check from Windows Explorer what files the emulator has saved to floppy disk, you must first close the emulator; otherwise Windows won't detect the new files on the floppy disk. The emulator entirely locks the floppy drive, so you can't access it from any other software while the emulator is still running.
For instructions on how to use the floppy drive, see The Enterprise Disk System Manual.

Using a floppy image
A floppy image is loaded into a virtual floppy disk drive (rather than a real hardware floppy drive). To create a floppy image Virtual Floppy Drive is needed.
A drive letter can be assigned to the image file in Options menu, Disk / Configure disk drives. Under one of drive a:, drive b:, drive c:, drive d: tick use disk image, then click insert button to add the previously saved image file. Use the remove button to remove the image file from the virtual drive.

Currently the EP128Emu is the most accurate Enterprise emulator for the PC and provides the most options, though it might seem complicated to use for beginners. This manual has been produced for them. We hope that after reading this manual anybody will be able to use this lovely emulator. The alternative is the EP32, which is also a great emulator, though with less options, but ideal for beginners because of its easy usability. The most recent version of the EP128Emu is 2.0.9.1. This is a rewritten version in C++ of the earlier EP128Emu v1.x.x written in C, with many more options to be set, with a better built-in debugger and with a more accurate emulation. EP128Emu is the work of István Varga. You can download it from here.
Downloadable ROM pack.

Installation
When installing the emulator, Source code and Download old ROMs don't need to be ticked by novice users. Source code is needed only for developing the emulator, and old ROMs are needed only if you want to use config files for older versions. Thus, if you are installing the emulator for the first time you can untick everything except for Download ROM images.
If you have already got the ROM files, you can also untick Download ROM images. However it is recommended that you download the ROM package because there may have been upgrades. ROMs are stored in the \Program Files\ep128emu2\roms directory, and all ROMs that are to be used should be put here. EPFileIO.rom is not used in real Enterprise machines, but makes it easier to load files into the emulator - for instructions see below.
If you have a Hungarian PC keyboard Use Hungarian keyboard map has to be ticked - otherwise you won't be able to use the keyboard properly. The question Reinstall ep128emu configuration files? must be answered OK for the first installation.
After installation two shortcuts will be found in the Start Menu: one for running in OpenGL mode, one for software mode. Certain video card drivers might cause problems in OpenGL mode, in which case the emulator must be run in software mode. The disadvantages of using software mode are that picture refresh rate is slower and some effects in the "Display / Configure..." window cannot be enabled, but software mode is compatible with all video card drivers.

Loading Enterprise programs into the emulator
There are several possible ways to load programs. Loading from tape is cute because it has the same tape sound as a real Enterprise machine. Thanks István for that!!
The easiest way to load a program is to use EPFileIO.rom, because no virtual cassette has to be edited and no floppy image has to be made. With a few clicks, programs can be loaded from the PC's hard drive.

EPFileIO.rom
This is a utility developed specifically for the emulator, to enable the emulator to access files directly from a directory in the PC. It works only if epfileio.rom is placed in segment 10 or higher. (This can be set in the Machine|Configure|Memory window). Also Enable virtual file I/O has to be turned on in the Machine / Configure / General window. The directory can be set in the Options menu Set working directory. For example, if the working directory contains a file named "bruce.com", you would load the Bruce Lee game from IS-BASIC by typing the command load "file:bruce.com". Games consisting of more files can also be loaded (except for games that use the default device to load). So EPFileIO.rom contains the FILE: device which enables the emulator to load files from the PC's hard drive. You can also save to the hard drive by referring to the FILE: device (if FILE: is the default device it doesn't have to be referred to).
The emulator loads files from the FILE: device (PC's hard drive) as default. Instead of FILE: device, a floppy disk drive also can be set as default by typing the command :def_dev_disk in the emulator's IS-BASIC. To set FILE: device as default again, type :def_dev_file.

Tape
First of all some background information is needed. When the Enterprise loads from tape, it decodes the "twitter" recorded on the cassette. Thus if you want to use an emulated cassette tape player for the emulated Enterprise you will need to generate this "twitter" somehow, and the Tape Editor utility has been made for this purpose. If you want to load any program from tape to the emulated Enterprise, the Tape Editor utility must be used first. (For how to use it, see the next section). Using Tape Editor, a sound file can be generated in the same folder as any file stored in the PC, and this sound file can be selected in the emulator's Machine / Tape / Select image file menu. It is the same as placing a cassette into the tape recorder of a real Enterprise, but of course when using an emulator we must use a virtual cassette. You can edit a virtual cassette using the Tape Editor (see next section). Note that although Tape Editor saves virtual cassettes with the .tap extension, the structure of this .tap file is totally different from the one used by the EPTE or TAPir utilities. Nevertheless Tape Editor is able to load EPTE / TAPir .tap files, and they can be used directly in the emulator. So, to play a virtual cassette (TAP, TZX, WAV), you would use Machine / Tape / Select Image and browse the menu. Then press F9 to play the selected virtual cassette in the virtual tape recorder. Now a letter P will appear in front of the counter in the top right corner, to indicate that the virtual tape recorder is in playback mode. Why has the counter not started? Because the virtual tape recorder works by remote control like the real one, and it starts only if EP needs it. You can easily check it by pressing F4 in IS-BASIC, but it is better to press F1 and start loading. Now "twitter" can be heard. If the files are placed in order, loading will be finished within a few minutes and the game will run.

Tape Editor
This utility converts any files on your PC into sound files for EP128Emu to load from tape. These sound files will be now referred to as virtual cassettes. Put the files of your favourite game (we will use Alien 8 as example) into a separate directory. Run Tape Editor. On the left side a big black area will be seen, and on the right some buttons.
Click Import, browse the directory containing Alien 8 then pick the first file. Which is the first file? Tape file sequence means that files follow one another in the order that they are loaded so you must put the files in order (sequentially). The right sequence is generally easy to determine by reviewing the list of files (.com, .scr, .prg, .rom). In some cases however you will need several tries to find the right sequence. Fortunately file sequence is easy to modify in Tape Editor using the up and down arrows. When you modify the sequence the virtual cassette must be saved again. The file sequence for Alien 8 is: alien_8.com, alien.scr and alien.prg. The completed virtual cassette can be saved to the PC by clicking the Save button after picking the destination directory. It's practical to save them to the emulator's "tape" directory in order to load them easily.

Floppy disk and floppy image
In the Options / Disk / Configure menu you can pick the image file (.img). To use the floppy disk in drive A: of the PC, \\.\A: has to be written as the file name, and the tracks, heads and sectors should be set to -1 (this is the default setting which generally doesn't need changing).

Tip: If you want to emulate a turbo machine, the following frequency values have to be set in the MACHINE / CONFIGURE menu, in the GENERAL page (in order to give accurate delays):

(These values assume 14237536 Hz as the NICK frequency.)
These values don't need to be entered each time you change the setting. Two optional settings can be saved in the MACHINE / QUICK CONFIGURATION menu (SAVE CONFIG 1 / SAVE CONFIG 2). Page Down / Page Up keys can be used to switch between the two saved settings, or you can select them by clicking LOAD CONFIG 1 / LOAD CONFIG 2 menu items.

COM

(COMMAND file) If you want to run a program, you have to look for a file with this extension. The COM extension refers to a file which can always be run, is in machine code, and can be loaded from anywhere (EXDOS, BASIC, WP etc.) Warning! CP/M programs also use the COM file extension, but these can be loaded only in IS-DOS!

BAT

(BATCH-file) Batch command file. This is a standard text file containing executable EXDOS commands (or other commands which can be interpreted by other system extensions). These commands are executed by the system one by one, when you run the file.

INI

Initialising (start-up) file (text file). A special variant of this is EXDOS.INI, which is run by EXDOS at each system restart.

BAS

BASIC file. A file containing a Basic program. It can be run by loading it into IS-BASIC. The Enterprise does not store BASIC programs as text but in a coded (tokenised) format.

ZIP

A loader (runnable file) for a program compiled by Zzzip. The extension is somewhat misleading as it is actually a BASIC program, so it is to be loaded in IS-BASIC.

A program file (not runnable) compiled by Zzzip. It cannot be run directly, but instead by runnning a BASIC loader (with ZIP extension).

PAS

Pascal source code. The Pascal program has to be compiled before running so a file with PAS extension has to be compiled into a runnable file with COM extension. PAS files can be loaded into the Pascal editor.

ASM

ASMON / ASMEN source file. This is a text file in assembly language, which can be loaded into ASMON / ASMEN for editing and assembly into machine code.

HEA

HEASS (program by Laci Haluska) source file. It's a text file in assembly language, to be edited and assembled into machine code using HEASS.

FEN

FENAS source file. It's a text file in assembly language, to be edited and assembled into machine code using HEASS.

EXT

This is an absolute system extension. One of the best features of the Enterprise's operating system is using system extensions. After loading an EXT extension file nothing seems to happen, but typing the :HELP command we can detect the new extension at once. Some system extensions run automatically after loading but this is not typical.

ROM

The EPROM burnable version of an absolute system extension (only the header differs). EPDOS can load it. The emulator also uses such files, so optional configurations can be created in the emulator using them. Warning! Do not confuse this with the ROM files found in some games converted from Spectrum! These files contain the Spectrum ROM - using them it is easier to convert a game, though the quality is low.

TRN

A game loader to provide eternal life (cheat). This is not a standard extension, but it's an Enterprise speciality. It can be found in games folders, enabling the game to be started with eternal life (eternal ammunition, etc.), so it is a runnable file.

WIN

EDC Windows application. This is the standard extension for EDC Windows applications. It can be started only after running EDC Windows, of course.

The file format for Enterprise Word Processor documents. Files written in WP (and saved by the SAVE command) should be named with the WP extension.

HWP

The file format for HWP, the best word processing software for the Enterprise (the work of Laci Haluska).

TXT

A standard text file. TXT files are not traditional on the Enterprise, but by using WP's PRINT command, for example, files "printed" to a disk can be created and called TXT files.

DTM

Digitrax Module file. These are MOD pieces of music converted from the PC. Unfortunately they can only be up to 64kb in size, which restricts the audio opportunities. They can be played using the Digitrax Module Player (see: Music heading here) or by the :DTM command of the Iview extension.

EPV

Video file, which can be played using IPLAY. (This program is also part of the Multiplay program pack.)

TOM

A compressed (game) program. The compression method was developed by Attus. It compresses simple sequences of the same byte occurring as consecutive data elements. It can be loaded using the DTF&TOM program.

DTF

Doubly compressed file. A further developed version of TOM. In the first pass it compresses simple sequences of the same byte occurring as consecutive data elements (like TOM), and then the output of the run-length encoding is further compressed in a second pass, using an optimal variable length encoding of byte values based on statistical analysis of the data. Decompression of DTF files is slower but the data compression is very efficient. Most games like this consist of a single file, but for multiple level loader games the individual levels may be stored in separate files. DTF files can be loaded using the DTF&TOM utility (it is fairly slow) or by using the command DL in ZozoTools. If you want to use the DTF&TOM loader, it is best to collect the DTF files together on common disks and copy the loader to all these disks (it does not need much room).

PCK

Compressed file. This compressed file can be created with the EPDOS command PP. The compression is less efficient than DTF but it is much easier to use. PCK files can be unpacked any time and EPDOS can load them.

SCR

Screen file. First of all, games have this file as their loading screen (in Spectrum format), but SCR can also be a format which can be loaded using the :VLOAD command.

PRG

Program file. Games often have files with this extension. It's a file containing a machine code program, but we can not run it directly. It can be run only by using a loader with a COM (or TRN) extension.

	CPU frequency	Video clock frequency	Sound clock frequency
4 MHz	4000000 Hz	889846 Hz	500000 Hz
6 MHz	6000000 Hz	889846 Hz	750000 Hz
7,12 MHz	7118768 Hz	889846 Hz	889846 Hz