Pokemon Rom problem

I have been trying to play a rom of Pokemon Red, but every time I try and load it, it tells me (unknown opcode) I don't know what this means?
also in the future if I want to rom hack my own copy of my rom to add things in end game such as Pokemon and battles, is this possible and would this change the checksum? like CRC/SHA, etc
and if I did change it in the future, how would I play the rom once I've hacked it, as I keep getting no luck in loading the rom, (checksums showing up as wrong) please helppp!!

Is this a fresh rom you just downloaded and didn't hack? Because unknown opcode means it got corrupted. IF you did hack it, you did something wrong.

longlostsoldier said:

Is this a fresh rom you just downloaded and didn't hack? Because unknown opcode means it got corrupted. IF you did hack it, you did something wrong.

Click to expand...

Thankyou for reply, I would like to play my Japanese roms of red/green/blue/yellow, but would like to add or translate (whichever is easier) to english text as such as character/rival names and in game text, would you know how i would do this and which tools i should use? thankyou!

Hm. Well, there is no Japanese dissassembly that I know of, so it sounds like you need a text tool - but if you want to translate all the Japanese, why not just use the English disassembly and build a rom already in English?

longlostsoldier said:

Hm. Well, there is no Japanese dissassembly that I know of, so it sounds like you need a text tool - but if you want to translate all the Japanese, why not just use the English disassembly and build a rom already in English?

Click to expand...

Do you think you can help me, which tools i need to download and a step by step on how to add/translate japanese pokemon roms to english? thankyou mate!

Literately the first thing that showed up on google was 'Poketext'. (A hex editor could also work, although I think you'd need a text table.) In future, try googling for basic information.
https://swamperttools.webs.com/downloads.htm
Then replace the Japanese text with English.

Alternatively, take an English disassembly and just modify it to be more like the Japanese version.

longlostsoldier said:

Literately the first thing that showed up on google was 'Poketext'. (A hex editor could also work, although I think you'd need a text table.) In future, try googling for basic information.
https://swamperttools.webs.com/downloads.htm
Then replace the Japanese text with English.

Alternatively, take an English disassembly and just modify it to be more like the Japanese version.

Click to expand...

thankyou for the reply, does poketext work with green, as it only lists red, blue, yellow, gold and silver?
all i have to do is replace the text? what would i do with the text after editing? thankyou!

longlostsoldier said:

Literately the first thing that showed up on google was 'Poketext'. (A hex editor could also work, although I think you'd need a text table.) In future, try googling for basic information.
https://swamperttools.webs.com/downloads.htm
Then replace the Japanese text with English.

Alternatively, take an English disassembly and just modify it to be more like the Japanese version.

Click to expand...

I cant seem to find a text editor for (japanese) only english, poketext doesnt work with japanese roms :(