Commodore CASSIOPEI, User Manual

Page: 67 / 76

11 Virtual file mode
The virtual file mode is intended to be used for cross development. In fact it was heavily used for
developing most of the code that runs on the CBM computers. What makes this mode so practical
is that it doesn't require you to adding/removing the created program to/from the filesystem
(because software is never right the first time). Therefore the eliminate this problem, the file
remains on the computer (PC) it is written on and loaded through the virtual file mode into the
memory of the CBM computer. This method does require some effort to setup correctly and is not
intended for the average user.
The way it works is as follows: the PC has to have a folder where the file virtual.prg is stored, that
folder is to be exposed to the local network using a HTTP webserver application like “mongoose”.
When the cassiopei (configured for the virtual file mode) has loaded it's fastloader routines it will
go to the ip-address of the computer and requests the file virtual.prg. Which is then loaded through
HTTP into the CBM.
In order to make this work you need a program to act like a local webserver. The program “HFS” is
a very simple program that does just that. It (HFS.exe) can be saved into any folder and directly
executed from there, it won't install any files onto your computer. It does have some settings as
shown below. Here you can specify the folder or add a file to the “root” you want to make available
through HTTP.
Above you see that the file “virtual.prg” has been added to the “root”, it was done using the
menu→Add_files… function. The port value is shown on the top of the screen and is default set to
80, a value which I prefer because this way I can quickly test the connection using my webbrowser
without having to enter (and remember) the port address.
Ofcourse you can use any other webserver application if you'd like, as long as the file is available
through your local network, personally I check this by using my webbrowser and type the IP-
address followed by the filename of the virtual file (192.168.2.8/virtual.prg) and if it works it will
2019-10-27 Page 67 of 76 CASSIOPEI v2.0