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I should watch the whole video and I'd get my question answered,

Well, I know that my solution is not perfect, I just wanted to be able to reset c64 using the keyboard (combination of keys) and I managed to do just that. In addition, I was using the stock C64 and never tested my solution with other Kernal ROMs or other sys cartridges. Thank You for the video suggestion and thank You for watching :) Cheers!

Yes, it would require much more coding but it would be fun to try :) ..and it could be crazy fast :) he he Thank You very much for watching :) Cheers!

Oh Yes, that was the thing back then and still is, if You want to speed up some parts of the BASIC code, just inject that part in the memory (machine code) and call it with SYS. And Yes, BASIC couldn't handle interrupts so for that You would need to use assembly/machine code for sure :) Cool! Thank You for watching :)

Well, those numbers are part of a BASIC code. I used Mikro Assembler cartridge so that I could write on C64 and compile and run the assembly code on C64. But, You don't need those numbers if you use some other assembly compiler. You can compile the code on a modern PC and then just run it on C64. For assembly language the labels are important. ...and those labels are converted to memory addresses during the compile process.

​@@JosipRetroBits I mean you had 10 loop lda $d020 20 adc #01 30 sta $d020 40 jmp loop Why not 20 loop adc #01 ?

@@nagyandras8857 Yes this is where I want to explain how lda and sta instructions work. This is not a good code :) A more efficient way would be to have a loop label on line 20, yes! But also, we have direct instruction if we want to increment by one, just direct "inc $d020". If we want a different increment value then we can use Your suggestion, Yes. Sorry, I didn't get what are you asking the first time :)

Yes it does and what I show in the video is just a very small amount of those routines :) Thank You for watching :) Cheers!

Thank You for your information, uuu, ok I need to check what is the problem with 31:03 on NTSC, to be honest, I didn't check if ti works on all systems. Cheers!

I think that will change my life tremendously :) Thank You for watching :) Cheers!

Glad you liked it and thank You for watching :) Cheers!

Thank You very much and thank You for watching :) Cheers!

@@JosipRetroBits if I just knew this back in the eighties.. those kernel routines are very useful. Back then it was really hard to get this kind of info and explanations. I only changed colors and did some sprites as an teenager in assembly. Could you even imagine what an impact it had if everybody had an assembler and this kind of kernel-routine info back then ..

@@Jemacaza Yes for sure. For comparison, the first time I used C64 was retyping some game from the magazine. I didn't understand anything :) Now it's so much easier to get information and to learn new stuff. And of course, You can develop and test your code on the modern PC before you run it on the real C64 and this much faster and easier way to do this. :)

Ha ha, that is awesome :) Oh, those are the first kit comp.? with just a numeric keyboard? Programming in machine code directly, You have my respect, Sir. :)

@@JosipRetroBits Yes, it's a kit from the time when you could not buy a computer in stores yet. A Netronics Elf II. I still used ut until I bought a Atari ST and still have it. You should take a look at the processor (a CDP1802) if you are really interested in 8 bit computers. Not exactly mainstream, more like RISC before that was officially invented.

Me too :)

Thank You very much :) Just to be clear, there are people in the retro community who have more knowledge and teaching capabilities than I do. I wish You the very best in Your retro journey and welcome aboard :) Cheers!

Thank You very much :) Yes I like MA too, I know it's way easier to develop on a modern machine these days but this feels so natural to me :) Cheers!

Sorry. It's KERNAL :) Thank You for watching :)

I suggest that you check your facts before offering such bombastic corrections. On the C64 it is and always has been spelled KERNAL. en.wikipedia.org/wiki/KERNAL

Thank You very much :) I really enjoy exploring C64 routines and I hope this video is interesting to watch :) Cheers!

KERNAL is Operating System on Commodore 64. Cheers!

@@Joel-qz6sd Yes, a bit more than that. but in general Yes. Kernal is simply an operating system on Commodore 64. It also takes care of all other operations on the system, like cursor, serial communication, time, etc.

@@Joel-qz6sd No, really, there's no such thing as a kernal. Perhaps you're trying to explain "kernel."

Glad you enjoyed it and thank You for watching:) Cheers!

Ha Ha, something like that :) Thank You very much :) Cheers!

Run/Stop key will not stop ML execution only execution of BASIC code. That is why I needed to implement STOP key detection to exit the program in my examples. Thank You for watching :) Cheers!

Yes, back then this was a very nice way to program/develop in assembly and compile/run on the same machine. Now it's way better to develop on a modern pc and then just test on C64, but I like this first method, don't know why, feels natural :) Thank You for watching :) Cheers!

I did pronounce that incorrectly, sorry about that. JSR is "Jump to Subroutine", or "Jump to Routine". Cheers!

Sorry about that. I had some issues with the audio in a couple of videos from that period. Cheers!

It is the same on PAL and NTSC machines, 1/60th of a second. (60 times per second) Sorry, maybe I didn't explain that very well in the video :) Thank You for watching, Cheers!

Yes, it is much easier today, and most of it has been well documented and disassembled so that we now "know" a lot more. I don't have many Commodore books but I never saw any routines explained anywhere in those books. Memory addresses Yes, but not routines. Thank You very much for watching :) Cheers!

Hi, not with machine code (assembly code). That only works with BASIC code. But I've implemented that option later in the video. Thank You for watching :)

@@JosipRetroBits that's weird because l remember RunStop/Restore working for ML unless it was specifically disabled. Hold down RunStop while you sharply tap RESTORE several times. I know the C64 needs a rapid transition on the restore key- usually several. Why, l don't know. But slow wrists were less successful. I suppose this could be a Mandela memory Effect since l haven't tried this is decades. But l could swear this triggered an interrupt that sends you back to the ready prompt. Try it and let me know.

@@saganandroid4175: Yeah, that's what I remember as well. I wonder why he never bothered to try it. I have just set my 128/64 back up and I have just re-encountered ones that have _disabled_ the restore key for exiting; and in fact, they restart the programs instead; and you can even soft-reset from 64 back into 128, run something there, and then soft-reset or go64 back into 64 and that program immediately restarts! BUT... if I remember right, it had to be specifically programmed to do that; otherwise what you were saying would indeed happen. I'll have to go through my disks and make a count list of some sort to see if we're right: which is the exception or the rule. And yeah, on an original 64 you do have to hit "restore" fairly hard. I don't know about the C, but on the 128 in either mode you don't. Why don't you set your 64 back up now too?

@@JosipRetroBits try it. Run your ML code. Hold down RunStop and nothing happens. Now while holding that key down, sharply smack the Restore key several times. That should generate a NMI. But on most C64s you need a quick sharp wrist action on the Restore key because only the trailing edge of that line is useful. Try it and report back.

@@saganandroid4175 Aaaa ok, got it! Thanks :)

Oh Yes, Thank You :)

Thank You Rudy :) I enjoy this stuff and I do hope I managed to share my enthusiasm with all of You :)

​@@JosipRetroBits Great video. I had a Commodore 16 in 1985. My classmate had a Commodore 64. Any idea where I can find the user's manual. There were very good Basic codes in that book.

Yes, it is so much easier to find and share information these days :) Thank You for watching ;) Cheers!

We didn't, so I've dashed your hope. Sorry.

Thank You :) EOR to get more random values in A. Whatever is in A we EOR with D012 and that will give more random numbers than just loading D012 :)

@@JosipRetroBits But the accumulator will always have the same value (255 / $ff) on each iteration due to your JSR to $FFE1, so I cannot see how that would increase randomness. Try adding STA $d020 in line 22 and you will see what I mean.

Ok will try. I never checked value in A when returning from $FFE1, but yes You are probably right :) Thank You!

Thank You :)

Thank You very much :) Cheers!

Thank You Steve :)

Thank You and thanks for watching :)

4EVA & EVA :) Thank You for watching :) Cheers!

Thank You :)

Sorry about that. I will send you here full code today.

I was explaining how "on goto" was used as "if then else" In case (g<28) is true; the result will be -1, so then we have "on - (-1) goto 2" which gives "on 1 goto 2". So it will jump to line 2. Once we reach 28, (g<28) is false = 0, then we have "on -0 goto 2"; we will not jump on line 2, but the rest of that line will be executed. ?"time our":end (game over) in short, it's a kind of replacement for if then else: on (condition) {then}: {else}

Nice to see this little tip still helps someone :). Maybe it's slightly different firmware, but if it works that is awesome :) This SD2IEC model is modified so that I can use it on C64, plus/4 and C16l. (It's still available to buy on ebay) Cheers!