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distractions

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brpocock

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Probably too many WSYNC's as placeholders in the vblank, but the combat kernel (still sans major improvements blogged earlier today) rolls my B&W test TV. (A 12" "LLOYDS" branded NTSC.) The 11" colour set -- a more modern (early '90s) Panasonic set -- displays a fine and steady picture, but it would be more tolerant of bad signal, being more recent. I think.

 

Note to self: adjust timing of vblank to use INTIM* rather than just throwing a shitload of WSYNC's in there.

 

PS: Note[2] to self: buy another EPROM, I don't think that leg is going to grow back :(

 

(It's been years since I pried one of these babies off, sorry baby... lucky I bought a spare before, but still sadness.)

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Holy hell, man, you are using WSYNCs to time VBLANK!? Are you using WSYNCs to time the overscan as well?

 

Switch to using the RIOT timer immediately!

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Holy hell, man, you are using WSYNCs to time VBLANK!? Are you using WSYNCs to time the overscan as well?

 

Switch to using the RIOT timer immediately!

 

OK, now, I understand the objection during VBLANK, as there's game logic running concurrently and it's extremely difficult to get the timing right on that sort of code.

 

But, why would it bother overscan?

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Holy hell, man, you are using WSYNCs to time VBLANK!? Are you using WSYNCs to time the overscan as well?

 

Switch to using the RIOT timer immediately!

 

OK, now, I understand the objection during VBLANK, as there's game logic running concurrently and it's extremely difficult to get the timing right on that sort of code.

 

But, why would it bother overscan?

You have this giant, complicated, tiled RPG and you don't use (and/or don't plan to use) the overscan for game logic as well? :)

 

Every game I've done has used the overscan for game logic, though perhaps Go Fish! didn't need to; probably it did. M-4 and Reindeer Rescue definitely needed that extra time. In fact, I had to do a lot of optimizing and juggling to fit all the game logic in!

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You have this giant, complicated, tiled RPG and you don't use (and/or don't plan to use) the overscan for game logic as well? :)

 

Every game I've done has used the overscan for game logic, though perhaps Go Fish! didn't need to; probably it did. M-4 and Reindeer Rescue definitely needed that extra time. In fact, I had to do a lot of optimizing and juggling to fit all the game logic in!

 

Actually, the drawing is complicated, the script interpreter is complicated, but ultimately the game logic is downright pedestrian.

 

EG: The tile draw code has one moving object under joystick control. That's it. Almost everything else is static.

 

The combat code is turn-based. The drawing is complex, but the logic involved boils down to rolling a dice once every 10 seconds or so.

 

At the moment, about 1/2 of the vblank is idle time. I think I had 20+ WSYNC's in a loop to pad it out... plus a couple of others embedded to do HMOVE's.

 

I wouldn't rule out using it, but ... it's so little time ... *shrug*

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Wow. In that case, then, no reason to use the timer vs. WSYNCs in a loop, I suppose, in the overscan.

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My goal there was originally to do matched-cycle work on every frame, i.e. have joystick and sound code that was constant-execution-time, but when I got down to it, it's probably going to be easier to just cap it off with the timer :)

 

PS: Yes, I realize that my above post is probably one that I'll be laughing about in a few weeks. "No need to use the overscan, but I forgot all about (---nightmare-here----)..."

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