sdltrs is a Radio Shack TRS-80 Model I/III/4/4P emulator for Linux, Mac
OS X, and Windows. It is a port of the very capable xtrs emulator for
Unix by Tim Mann. It includes lower case, the real time clock, hi-res
graphics, serial port, parallel printer, mouse, cassette, sound and
5" and 8" floppy disk drives in single and double density, and even
hard disk drives. The emulated floppy and hard disk file formats are
compatible with the popular MSDOS-based emulators by Jeff Vavasour,
Matthew Reed, and David Keil, and (if you choose a capable enough file
format), all features of the original TRS-80 floppy disk controller are
Why did I write another emulator? Several reasons. First, and foremost,
there was no TRS-80 emulator available for Mac OS X. Since I am the
of Atari800MacX, which is based on libSDL, it made it easy for me to
a TRS80 xtrs port based on SDL, so it would run on Windows and Linux as
well as Mac OS X.
Second, sdltrs provides a text menu based GUI, which is more user
friendly interface than the interface
xtrs provides. Finally, sdltrs provides some other enhancements
to xtrs, such as the ability to copy and paste from the host to/from
the emulator, the ability to save and load the emulator state, disk indicator LED's, and on
the Mac, to emulate an Epson printer as well.
There is a lot of help available in the other html pages of this help
have links available at the top of the screen. Since it is based on
xtrs, Tim Mann's web page is also a good resource
ROM images for Model I/III/4 are available elsewhere on the Web.
I do not know the copyright status of these ROM images, and I have no
connection with the sites that offer them. Some MS-DOS based TRS-80 emulators
come with Model I and Model III/4 ROM image files. These files will
work in xtrs too.
Alternatively, for Model III or Model 4 emulation, xtrs can use a
MODELA/III file as its ROM image. This is not identical to a real Model
III/4 ROM, but is close enough that almost 100% of TRS-80 programs will
work with it. The LS-DOS
6.3.1H operating system disk that I have permission to distribute
includes a MODELA/III file. You can boot this operating system using
xtrs's Model 4P emulation and export the file for use in Model III and
4 emulation, or for convenience, click here to
download the MODELA/III file directly.
For Model 4P emulation, you can use Pete Cervasio's free minimal
Model 4P boot ROM, now supplied with xtrs; however, the free ROM can
boot only Model 4 operating systems (not Model III), and only from
floppy disks. The original Model 4P boot ROM is copyrighted software,
but if you own a Model 4P, you can copy its boot ROM onto a floppy for
personal use using the instructions and tools in this article,
originally published in the Misosys Quarterly 1.2. You can also buy
Frank Durda IV's improved Model 4P ROMs from M. A. D. Software.