It is currently Sat Oct 21, 2017 3:32 am

All times are UTC - 7 hours





Post new topic Reply to topic  [ 2 posts ] 
Author Message
PostPosted: Tue Dec 27, 2005 8:03 am 
Offline
User avatar

Joined: Sat Feb 12, 2005 9:43 pm
Posts: 10065
Location: Rio de Janeiro - Brazil
Hello people!
I got a quick question: Is there any limit to how often you can bankswitch? I'd guess there isn't, but I'm asking just to be sure. I want to do something like this: say I have a ROM bank with a level map. And another bank with tile maps for objects and their animations. So I'd use the level information and right after I'd use the object information, once per frame. There probably isn't anything wrong with it, as I've seen games switching CHR ROM one or more times in a frame.

What if I were to switch much more frequently than this? Like, say I got a table holding the results of a 7-bit multiplication. One 16k bank holds the low bytes and another one holds the high bytes of the result. Could I perform a series of multiplications, changing the banks for each one? I do not intend to do this, this is just an example of very frequent bankswitching.

Thanks for the help!


Top
 Profile  
 
 Post subject:
PostPosted: Tue Dec 27, 2005 8:42 am 
Offline
Site Admin
User avatar

Joined: Mon Sep 20, 2004 6:04 am
Posts: 3470
Location: Indianapolis
Nope, no limit really. Logic chips are a lot faster than the NES ROM access speed, so it'll have the new bank switched in before the NES is ready to read the next byte.

It's different on a cart like Squeedo, takes a little longer since the mapper is a microprocessor rather than logic. I think that's a unique case though.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 2 posts ] 

All times are UTC - 7 hours


Who is online

Users browsing this forum: No registered users and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group