The way BASIC 65 has become in the meantime, I find it really fast and comfortable to use for the MEGA65.
However, with all innovations and extensions of the BASIC I still missed possibilities to be able to proceed with the programming a little more structured than with the notorious "Commodore BASIC spaghetti code".
From this the idea matured, I try to build this into the ROM in some way. Because I first tried if it will works at all and how and why, I made a fork from ROM version 920300 (from January 22nd 2022) and from here on I started an independent development of BASIC 65, also independent from the official MEGA65-ROM.
So everything from ROM 920300 on, is no longer from the MEGA team, but is grown on my crap. So nothing with "an official MEGA65 release" or so. No, it's only "Snoopy made".
In the ROM is unfortunately hardly more memory space, in order to accommodate something. So it is not so easy to squeeze a handling for procedures onto this "filled BASIC".
I tried it the last few days and with a few restrictions it works fairly good now.
And to make it visible at the start of the extended ROM (and because I like it), I made the font (FONT B) and the design based on the Commodore 8000 series with their BASIC 4.0.
If you prefer the blue-white design with the standard character set of the MEGA65, you just have to press the F6 key (or F8, if you want it to be "green" again).
As a name to distinguish it from the BASIC 65, I couldn't think of anything better than "BASIC 65.EX", where the EX stands for "Extras".
And these extras all refer to the new commands that allow programming with procedures and local ("fast", numeric) variables.
That would be in alphabetical order DEFPROC, ENDPROC, LOCAL, RLEVEL and RPROC.
A small PDF describing the new commands is available here
https://65site.de/downloads/BASIC_65_EX_Additions.pdf
and in German here
https://65site.de/downloads/BASIC_65_EX_Ergaenzungen.pdf
For legal reasons I can't just offer the complete ROM for download, because it is based on the original C65 ROM from Commodore.
On my page
you can easily get a patched ROM and download it from there. For this you need an original C65 ROM in version 911001. Please make sure that the file has either the extension ".bin" or ".rom" and upload it to the patch page.
If you have uploaded the 911001 ROM (Attention: It is already checked thoroughly if it is the right ROM!), then the file will be patched and you will be offered the final product for download. Then rename the file (currently: "220211.bin") to "MEGA65.ROM" and load this ROM into the MEGA65, Nexys board or xmega65 emulator.
You can download a D81 image with short example programs here:
https://65site.de/downloads/BASIC_65_EX_Disc.d81
I will surely add some examples and correct some errors.
Here is an example (is also on the disk) "Recursive Tree", which shows graphically the possibilities of recursive use of the procedures.
If you want, you can also just watch the short clip:
https://65site.de/downloads/basic65ex_recursive_tree.mp4
If you want to try it out, have fun!