lgb.hu :: Enterprise-128 :: JSep - JavaScript Enterprise-128 emulator

JSep is a highly experimental work-in-progress Enterprise-128 emulator written in JavaScript for decent, modern browsers (Internet Explorer is problematic, but see below). It's my attempt to create an Enterprise-128 emulator using only web techologies.

It's a seriously modified and extended version of the great JavaScript ZX Spectrum emulator, JSSpeccy. The core Z80 emulation is the same, but other parts are written by me, and there is some minor code which is seriously modified version from JSSpeccy. Though it's still important to note that the whole idea, the Z80 emulation and possible other fragments is from JSSpeccy. Big thanks to JSSpeccy's author and for the choosen software license! Of course my work is also a GNU/GPL software. Note: where I speak about JSSpeccy. I mean the old JSSpeccy version, not the new (v2) one!

Try it on-line here (no Internet Explorer, please!)
Download!

It requires quite modern browser. Really. It won't work with Internet Explorer, maybe you have some hope with IE 10 though, but it surely won't work with earlier versions (IE is very slow to adopt new web techologies - I can't even understand why people want to use IE still ...). I usually test the emulator with Google Chrome (version 29) and Firefox (version 23), and sometimes with Opera too (version 12). As far as I know newer (version 15?) Operas will use about the same rendering engine as Chrome, but I am not sure about the JavaScript engine. Short (and not complete) list of needed browser capabilities: canvas support, canvas putImage interface, ArrayBuffer JavaScript typed arraies, new Date methods, XMLHttpRequest AJAX (it won't work via ActiveX) interface with ArrayBuffer support.

Since it's a highly work-in-progress project, I suggest to try with Chrome as well (lastest version) if you use firefox and vice versa.

TODO list

Better time sync
Support "unofficial" nick modes (eg non 2 colour character modes) too
VSYNC handling should be better
RESET does not work for some reason during the last major modification
[DONE] EXDOS ROM is in the emulator but it lacks the hw emulation
On-the-fly program fetch mode and/or snapshot running
[PROGRESSING] Dave interrupt latch is emulated now, VINT, 1HZ interrupt works, no TG/etc interrupt yet though
So, of course no sound, since there is not so much Dave support
More optimized, polished code
Memory access is always on full speed even towards VRAM

NEW: Emulator configuration

The emulator supports some kind of "netconfig", which means the URL can hold configuration for the emulator. As JSep is designed a web application can be "launched" via an URL, this is the natural method, and made it easy to be referenced on other pages, etc

Warning: the netconfig interface is experimental! Do not expect to have proper error filtering, so you should not try use options with bad syntax, otherwise you will get javascript error(s) :-)

Example: http://ep.lgb.hu/jsep/demo/?mem=512&disk=no

mem tells the amount of RAM installed. It must be between 64 and 2048, and must be multiple of 16.
disk tells the URL of the disk image to use, or no to disable
diskhack is tricky. The value of this can be use or load. If this option is mentioned it's expected to use the disk option as well, then the meaning of disk is modified: the disk option will mean an EP program not a disk image! JSep will fetch the program and creates a disk image on-the-fly containing that file. The value of use simply means to use a disk image contains the file. The value load causes JSep to also create an EXDOS.INI file which auto starts that file.
exos tells the URL of the EXOS ROM image to use (you can imagine it's not worth to tell no here ...)
basic tells the URL of the BASIC ROM image to use, or no to disable (you don't want BASIC, or your EXOS ROM contains it already)
exdos tells the URL of the EXDOS ROM image to use, or no to disable
autostart should be used with value of yes to automatically start emulation (you don't need to click on the run button then), do not confuse with the autostart funcion of diskhack=load it's about autostarting a program inside Enterprise, not the emulator!

If an option is not specified, the default value is used which can also mean the usage of files from ep.lgb.hu server. But otherwise, JSep always fetches data from the net, even the EXOS rom image, so it's not a very brilliant idea to try to disable EXOS with no, as machine won't boot without any ROM image ...

If you specify some file name _without_ http:// or such where URL is expected then the image is tried to be downloaded from ep.lgb.hu server, so be carefull with this! By the way, you can examine the binary files here, which are used by the emulator. Without proper URL files are fetched from here (which is also the default case for ROM images etc, if you don't specify other values).

If you have a disk image which can be accessed via HTTP (or https or ftp, though they are not tested at all), you can tell JSep to use it. If you also make some EXDOS.INI to launch a problem, you can have an autoload function, by clicking on a single URL to configure+start JSep, your program will start within the emulator after booting. You can also auto-start a single file program with the help of diskhack=load option.

JSep will guess the geometry of the disk image based on its size. It will warn you if it was not successfull. Note: disk images are always treated as double side disks!

Of course, if you disable EXDOS (exdos=no, or non-existing ROM image is given, etc), not even program fetch (diskhack) will work as it operates with on-the-fly created disk, so EXDOS is needed to access it then!

Though this configuration interface seems to be "rough", using URLs is the natural way to provide linkage capability with other pages, so you can refer the emulator from other page. Of course a frontend can be written which uses nice html FORMs to construct URL for the emulator.

Before you ask: no, it's not possible to provide your disk image / ROM / etc from your computer, since it's a web/javascript emulator it needs data from the web. It's not possible to access your local disk from a web page, it would be dangerous if you think about this, so it's forbidden by design of javascript, for example.

Examples:

The following URL will cause to configure the emulator to use 128K of RAM, start emulation without pressing the "run" button, fetch program file from ep.lgb.hu, and start to run it automatically within the emulator:

http://ep.lgb.hu/jsep/demo/?disk=eprimo&diskhack=load&autostart=yes&mem=128

You can try to click on the link as well to try it. Here, the disk option specifies a program file instead of a disk image (because of diskhack option is used as well), the URL for file is "eprimo". As I've written above this causes to fetch data from ep.lgb.hu if it's not a "full" URL. The file in this example (eprimo, visit this link) is a work-in-progress Primo emulator for Enterprise. It's funny to have an Enterprise running within a JavaScript based emulator which runs a Primo emulator inside :)

Nice Enterprise slide show: CLICK HERE.

Some simplier examples (without loading/disk tricks), click on them: