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Annoying Robot

01:26

I was wondering if there existed a way to fix the difference in the running speeds of a PAL NES to run on TV's in the United States? Be it some converter or messing with the NES itself.

7 hours later…

wizzwizz4

08:14

@JAL Your review was fine; you don't have the ability to convert things to comments. Although I might have gone with outright deletion had the user not been now to Retrocomputing.

4 hours later…

Igor Skochinsky

11:53

@JAL: saw a link to your SE in "Hot questions", decided to join

Chenmunka

@IgorSkochinsky: It's good to see you here.

3 hours later…

JAL

14:34

Cool @Igor, which one? Was it the NES opcodes one?

Mods and other power users: lots of traffic coming to my NES NOP question due to reddit: reddit.com/r/programming/comments/5gjons/…

Chenmunka

I'd noticed its views going up rapidly

JAL

14:52

@Chenmunka while you're here, what are your thoughts on this answer? I feel like it has some good content, but it might be too meta.

Also thank you for the chat star, I think that would allow me to earn the Talkative badge

Chenmunka

That answer is true - I used to do the same thing occasionally. However, it doesn't really address why an undocumented NOP is used.

I'd be prepared to leave it as a first answer, maybe with a comment.

JAL

Ok, I'll add an additional comment

Chenmunka

The only reason I haven't answered that question is the same reason - I can't think why they would use undocumented as opposed to documented NOP.

JAL

Ah I see. I think the code signature answer is a great one. I hadn't considdered that.

3 hours later…

Igor Skochinsky

18:04

The Windows hotpatching used a two-byte nop (mov edi, edi)instead two one-byte ones to ensure that the instruction pointer would never point between the bytes and crash the process on resuming execution after patching. Kinda doubt it's the reason here though

JAL

@IgorSkochinsky You could post that as an answer, it's still useful information

I guess we'll never know for sure, since I doubt we could track down anyone who worked on the processor who remembers why they wrote the instructions the way they did

2 hours later…

Annoying Robot

19:41

Q: How were Western computer chips reverse-engineered in Soviet Russia?

The British ZX Spectrum computer had many clones in the Eastern Bloc. It seems many of them were built using Russian-made chips from the Angstrem factory in Zelenograd in/near Moscow. The Russian Wikipedia mentions the КР1858ВМ3 which is a Z80 clone, and the Т34ВГ1, which is the same thing as a Z...

zx-spectrum z80 reverse-engineering

Igor Skochinsky

reddit.com/r/programming/comments/5gjons/… claims it was anti-disasm trick

2 hours later…

Annoying Robot

21:21

Q: Why is my Sega Genesis/Mega Drive II got frozen?

My Sega Genesis/Mega Drive II get stuck (the image on the screen seems frozen) after some incidents that occurred to it. It doesn't matter when that is happened, which game did I play or even how hot is it get. For instance, it happened when it bump from something, like from moving it the slighte...