Hi65: a high-level Commodore 65 emulator
created by Devil Master


History - About - Screenshots - Downloads


Please consider a donation if you use Hi65 and would like to support future development. Thank you!
History
What's new in version 3:
* Fixed a bug in the function that loads the configuration: if a configuration file was not found, the program used to crash; now instead it creates a default configuration file.
* Rewrote the part of the PRINT function that deals with numbers, to make it display non-integers correctly.
* Modified the functions that work on non-integers so that they use doubles instead of floats, to increase precision.
* Made a major overhaul to the Windows frontend, which now allows you to write and modify BASIC 10 programs directly, instead of relying on an external text editor. The GUI of the frontend is now different too, more complete and professional. To reflect the change, the name of the frontend is now Hi65 Edit and Launch Tool.
UPDATE: Fixed a resizing bug in the frontend. Corrected the icons when another version of Commodore BASIC is selected.

What's new in version 2:
* Fixed a bug in the expression evaluator, so that goniometric functions also accept variables (only numeric, of course).
* Fixed a bug in the CHAR function, so that it also accepts variables (only strings - a limitation of the original instruction on the C65).
* Fixed a bug in the function that reads the instruction end address, so that it is also read correctly whenever its least significant byte happens to be zero.
* Added the support for more HD resolutions.
* Added the support for windowed mode. Note that running Hi65 from the launch tool will modify the configuration file to force it to full screen anyway, because launching it in windowed mode from the launch tool would cause it to crash. Instead, configuring it to any mode (windowed or full screen) with hi65cfg.exe and then running hi65.exe will run it correctly in whatever mode you select.
* Added a flashing cursor whenever Hi65 is accepting keyboard input.
* Added a wraparound check that returns the text cursor to the top of the screen whenever the bottom of the screen is reached.
* Implemented 1-dimensional arrays for numbers and strings, with a maximum number of 256 elements (from 0 to 255). This also includes the ability to use an element of an array as an index in a FOR cycle, which was not possible in an actual C65.
* Just for fun, added alternative interfaces to the emulator, resembling screens of other Commodore computers. To try them, use the following commands: GO64, GO128, GO16, GO20, GOPET. To return to the classic interface: GO65. Note that the changes are merely aesthetical, with no difference in functionality or scope of the emulator.

What's new in version 1:
* It can load programs at launch time, by specifying the name of the program as a parameter in the command line
* It can load programs at run time, by using the DLOAD command
* It can run a consistent subset of BASIC 10 instructions, although, for now, mathematical expressions need to have at most one operator
* It can perform extremely fast graphical operations, with an accuracy and speed exceeding those on MESS or on a physical Commodore 65 of various orders of magnitude.


About
The Commodore 65 is an unreleased computer from Commodore featuring 256-color graphics, a 3.54 MHz processor and a maximum of 8 MB of RAM.

Hi65 is a high-level Commodore 65 emulator.

In order to understand what "high-level" means, let's first consider what a "low-level" emulator does. It implements a software version of the whole machine, including a virtual processor that executes machine language commands. When any software for the target platform is loaded into the virtual RAM, the virtual processor executes it instruction by instruction.
However, the Commodore 65 is not the ideal platform for a low-level approach: each of the few units around has a different implementation of its ROM software, the implementations themselves are buggy and there is no commercial software around. The authors of MESS want to emulate the Commodore 65 with a low-level approach, but that has been a failure: the C65 driver of MESS has had the same bugs for over a decade, bugs that do *not* appear in the actual C65 prototypes. Emulating the Commodore 65 with a low-level approach is not "accurate" and it's more than pedantic: it's a self-defeating task.

Enter Hi65.

Hi65 does not implement a virtual version of the 4510 CPU (used in the physical Commodore 65), nor does it execute machine code software: it executes tokenized BASIC 10 programs directly, as if the various BASIC tokens were machine code instructions for its own virtual processor. Thus, the execution is much faster because it's not limited to the clock speed of the 4510 (but the timing is still accurate) and it's not limited by the scarce knowledge of the inner workings of the Commodore 65, because all instructions are made to do what the manual says they should do, not what they actually do on a physical machine (which may be buggy and inconsistent between individual machines).

The high-level approach makes Hi65 much faster than MESS, and even faster than the original machine. The gfxdemo1 program is completed correctly in a tenth of a second in Hi65. The same program takes 4 minutes and 44 seconds to be completed on MESS 0.106 with throttle off. This means that the high-level approach chosen with Hi65 makes it 2840 times faster than MESS. The same program is completed in about 20 minutes on a physical Commodore 65, which means Hi65 is 12000 times faster than a physical Commodore 65.

Hi65 (the emulator), Hi65CFG (the configuration software) and Hi65 Launch Tool (the graphical frontend) are released under version 3 of the GPL (GNU General Public License). If you do not have a copy of the license, go to http://www.gnu.org/licenses/gpl.html to read it.

Screenshots:
name.prg
gfxdemo1.prg
gfxdemo2.prg
gfxdemo3.prg

clock.prg
Downloads
Emulator:
Download Hi65 v3 (1161 KB)

Example programs:
Download name or read the source code
Download ssample or read the source code
Download gfxdemo1 or read the source code
Download gfxdemo2 or read the source code
Download gfxdemo3 or read the source code
Download clock or read the source code