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opcode last won the day on June 30 2020

opcode had the most liked content!

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About opcode

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    River Patroller
  • Birthday 12/20/1970

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  • Custom Status
    Bringing new life to your ColecoVision!
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    MA, USA
  • Currently Playing
    Penguin Adventure, Gradius
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    Donkey Kong Arcade

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  1. opcode


    We are sending invoices for the color line, please be patient.
  2. Call uses 3 bytes. First byte is the opcode, then the address (2 bytes). If the 1st byte gets corrupted, then you no longer have a call. Depending on the opcode you get instead, the address bytes can become other opcodes. Now, if the address gets corrupted, then you will call some random routine. The game could crash, or you could be “lucky” and it calls the very end of some harmless code followed by a Return opcode. Sent from my iPhone using Tapatalk
  3. But yeah, if it is just 2 bytes, chances are it corrupted a call and the new instructions are mostly harmless.
  4. Well, that isn't the listing. But anyways, looks like someone already fixed it. Unfortunately I am just too busy to disassemble right now, but I can do that eventually, when I get to create the SGM2 remaster version.
  5. Can you post the listing here? I can take a look Sent from my iPhone using Tapatalk
  6. Comparing the two versions should be fairly easy to “fix”. Disassemble, compare, “fix”. It is possible that it got corrupted but was still “working” mostly. For example, if a call instruction gets corrupted, it can become a bunch of harmless other instructions. The game still runs, but whatever the call routine was responsible for will no longer run. Sent from my iPhone using Tapatalk
  7. Are you a F18A shareholder? I didn’t state anything wrong. You don’t know anything about the game, but you felt you had to get involved. The only one arguing here is you. I stated all my reasons when asked. But it seems you didn’t like my reasons, you had to prove how easy F18A is. I am aware of the F18A internals because guess what, I have been using it since 2016. I just don’t want to learn TMS9900, especially (and this is the important part), especially when I have my own solution that does the same with a single setting. And for a game that already has 2 different engines. Now please go find someone else to pester. Sent from my iPhone using Tapatalk
  8. Please read my comment above. I think I gave enough reason for my decision. Don’t feel like doing 3 versions of the game, what is required to run smoothly at 3.5MHz, etc. It is all there. Gradius SGM1 supports optimized color palettes with F18A. Sent from my iPhone using Tapatalk
  9. You need for “split screen”. Sent from my iPhone using Tapatalk
  10. Grazi had to pause pre-orders, but it will happen.
  11. There are ongoing negotiations about that. So I can't give you an answer right now unfortunately.
  12. Yes, F18A can do smooth scrolling, but it isn't that simple. The whole engine must be changed, and I just don't have the resources to create 3 different engines. For example, F18A uses a TMS9990 or whatever CPU as the graphic coprocessor, and I don't feel like learning it. My own co-processor is much easier to understand and program. You must remember that the F18A was created with the TI99/4A in mind, while the AVSC1 inside the SGM2 was created specifically for the ColecoVision. In fact, the huge difference between graphic engines explain why in this case I am not doing a single version of the game. Gradius on SGM2 is a very different beast, and the video you have seen was just a preliminary version. A radical change of the engine is require in order for the game to run at 3.5MHz. One requirement is to replace all tile enemies with sprites, something I can't do with the F18A. Finally, I don't know how liking a post about you looking forward to smooth scrolling means that I committed to smooth scrolling on F18A. I understand your frustration, just please don't blame me for that.
  13. No, unfortunately smooth scrolling isn't possible with the ColecoVision video chip. Performance improvement is exactly what it says, an improvement in performance. That means the game runs with very little slow down. Graphic improvements are new colors in stage 1 and 3, and the proper "jumper" enemy in stage 1 (the original version had a single "jumper" enemy for all stages, but the arcade uses a different "jumper" in stage 1). Bug fixes include fixing the Vic Viper explosion when running in Phoenix/F18A. Phoenix/F18A also includes optimized color palette.
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