Wrathchild Posted September 2, 2009 Share Posted September 2, 2009 During the bank holiday I revisited a disassembly I'd done a while back and debugged it to patch up lookups etc and here's the result. Basically the BBC code is sitting 1:1 at the same memory addresses it does in the original. All I've tweaked was the following: - Added a Gr.0 Dlist that maps to fonts that represent the screen memory of the BBC. - Changed the playfield to narrow width as this appears to model the mode the BBC screen is using. - replaced BBC O/S calls with RTS for now. - used the font from my C64 port as the BBC uses its own ROM set and this doesn't map (easily) to the default A8 set. - moved Page 3 memory used by the game to $8300. What I note about this quick port is that the aspect ratio on the BBC differs from the A8 and so the view is filling the whole screen without even drawing the scanner section yet! I'm currently trying to re-place the BBC keyboard scan routine with an A8 one in order to progress some of the game logic, i.e. pressing a key now takes you to the commander summary screen but you can't yet press a key to bring up the different views, e.g. planet/market stats. Regards, Mark elitebbc.zip Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted September 2, 2009 Share Posted September 2, 2009 Mark! Go for it... Go!!! Quote Link to comment Share on other sites More sharing options...
Rybags Posted September 2, 2009 Share Posted September 2, 2009 It'd be a nice addition to the list of finally released games that should have been done in the first place. What mode on BBC does it use? I'd have thought it'd be 320x256 or similar. Quote Link to comment Share on other sites More sharing options...
xxl Posted September 2, 2009 Share Posted September 2, 2009 :-) nice. Quote Link to comment Share on other sites More sharing options...
Tezz Posted September 2, 2009 Share Posted September 2, 2009 I think you've made a lot of people's day Mark! Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted September 2, 2009 Author Share Posted September 2, 2009 Thanks. What mode on BBC does it use? I'd have thought it'd be 320x256 or similar. It is a split mode of MODE 4 for the view and MODE 1 for the panel. I'm no great BBC expert but these both state 320 x 256 in 2 and 4 colours respectively, however the Mode 1 appears to be coming out OK at 256 pixels. Maybe the BBC has a narrow mode too? Makes sense in a 3D game as presumably it makes the drawing calcs a lot easier (256 being a power of 2, rather than 320). I'll see if I can get a view of the panel 'as is' later. Quote Link to comment Share on other sites More sharing options...
Rybags Posted September 2, 2009 Share Posted September 2, 2009 I'm not sure if the BBC can alter it's width... I didn't even think it could do Mode splits. Quote Link to comment Share on other sites More sharing options...
Poison Posted September 2, 2009 Share Posted September 2, 2009 hi, I dont know if is this known but there is another verzion of Elite (demoversion). Elite.zip Quote Link to comment Share on other sites More sharing options...
AtariNerd Posted September 2, 2009 Share Posted September 2, 2009 You coder folks never cease to amaze me. Really. I would never have thought this possible. 8-O Yikes! Quote Link to comment Share on other sites More sharing options...
walter_J64bit Posted September 2, 2009 Share Posted September 2, 2009 Does this run on NTCS A8's? Quote Link to comment Share on other sites More sharing options...
Wrathchild Posted September 2, 2009 Author Share Posted September 2, 2009 hi, I dont know if is this known but there is another verzion of Elite (demoversion). I couldn't get that zip to work (7-Zip reports 'unsupported compression mode'). Remember just to press the 'Start' key and not normal keys. Do you mean one of these: Atarimania, Fandal or Ian Bell? Does this run on NTCS A8's? The BBC port should be OK, the C64 one has more lines though... works under emulation in NTSC but can't confirm real H/W. Quote Link to comment Share on other sites More sharing options...
Poison Posted September 2, 2009 Share Posted September 2, 2009 hi, I dont know if is this known but there is another verzion of Elite (demoversion). I couldn't get that zip to work (7-Zip reports 'unsupported compression mode'). Remember just to press the 'Start' key and not normal keys. Do you mean one of these: Atarimania, Fandal or Ian Bell? Does this run on NTCS A8's? The BBC port should be OK, the C64 one has more lines though... works under emulation in NTSC but can't confirm real H/W. yes atarimania and fandal are the same. Quote Link to comment Share on other sites More sharing options...
PeteD Posted September 2, 2009 Share Posted September 2, 2009 A "Nice" from me too Quote Link to comment Share on other sites More sharing options...
TMR Posted September 2, 2009 Share Posted September 2, 2009 I'm not sure if the BBC can alter it's width... It can yes, it's possible to feck about with the screen dimensions quite a bit if memory serves, very similarly to the VIC 20 (which can set X and Y sizes for screen and position it) if some of the effects i've seen are anything to go by. Quote Link to comment Share on other sites More sharing options...
JonnyBritish Posted September 2, 2009 Share Posted September 2, 2009 I'm not sure if the BBC can alter it's width... I didn't even think it could do Mode splits. Coming from the UK :-) I ma pretty sure the idea of mode splits is an Atari thing. The BBC and Electron cannot do this. Also as someone who played Elite way to much on the BBC in England I am more thana little interested in trying this out on my 130XE :-) Great stuff Quote Link to comment Share on other sites More sharing options...
TMR Posted September 2, 2009 Share Posted September 2, 2009 Coming from the UK :-) I ma pretty sure the idea of mode splits is an Atari thing. The BBC and Electron cannot do this. The BBC at least can mode split (i'm not sure about the Electron, haven't looked properly at the hardware) and there are a few games that use it. Quote Link to comment Share on other sites More sharing options...
PeteD Posted September 2, 2009 Share Posted September 2, 2009 Yeah, beeb can do mode splits, see Revs (something the buggered up emulators for a long time) and there are some others. Pete Quote Link to comment Share on other sites More sharing options...
emkay Posted September 2, 2009 Share Posted September 2, 2009 Can someone tell me why in all the huge space of the Internet is no rendition of "the blue danube" in MOD format available. Or , at least, a clean 3 channel SID to MOD converted track ... 1 Quote Link to comment Share on other sites More sharing options...
Heaven/TQA Posted September 2, 2009 Share Posted September 2, 2009 and if it will really come alive... there must be room to do at least double buffering... should be not a big deal on A8 and a custom VBL? 1 Quote Link to comment Share on other sites More sharing options...
JonnyBritish Posted September 2, 2009 Share Posted September 2, 2009 and if it will really come alive... there must be room to do at least double buffering... should be not a big deal on A8 and a custom VBL? On the subject of Elite, the BBC had a box that could be added to give a coprocessor using a connection called the tube. There apparently was a version of elite written to use the extra processor. Sort of reminds me of that box for the Atari that was never released where you could add additional processors Quote Link to comment Share on other sites More sharing options...
Rybags Posted September 2, 2009 Share Posted September 2, 2009 The extra CPU addon would have had the Atari just slaving as a keyboard + video display device. Despite the good intentions with the PBI/ECI, the architecture still doesn't really lend itself to coprocessors, or anything much that shares the onboard memory via DMA. Pity really... all they needed to do was output the HSync, and an addon could theoretically know which (few) cycles on any possible scanline are guaranteed to be free for DMA. Quote Link to comment Share on other sites More sharing options...
TMR Posted September 2, 2009 Share Posted September 2, 2009 The extra CPU addon would have had the Atari just slaving as a keyboard + video display device. That's pretty much what happens with the SuperCPU for the C64 as well, but the Tube really is a co-processor - there's something of a bottleneck in the design from what i understand, getting data back and forth to the external CPU is quite fiddly...? The Beeb is a pretty flexible beast though, i've seen a Master connected to a SID chip that simply runs C64 music code and then mirrors the registers into where the SID is mapped. =-) Quote Link to comment Share on other sites More sharing options...
JonnyBritish Posted September 2, 2009 Share Posted September 2, 2009 The extra CPU addon would have had the Atari just slaving as a keyboard + video display device. That's pretty much what happens with the SuperCPU for the C64 as well, but the Tube really is a co-processor - there's something of a bottleneck in the design from what i understand, getting data back and forth to the external CPU is quite fiddly...? The Beeb is a pretty flexible beast though, i've seen a Master connected to a SID chip that simply runs C64 music code and then mirrors the registers into where the SID is mapped. =-) Not Atari but on a similar subject..i read a while back that Magnetic Scrolls who wrote adventure games like The Pawn and Guild of Thieves actually could use the processor in a Commodore 64 disk drive like a co-processor At some point I really must purge this trivia from my mind :-) Quote Link to comment Share on other sites More sharing options...
PeteD Posted September 2, 2009 Share Posted September 2, 2009 The extra CPU addon would have had the Atari just slaving as a keyboard + video display device. That's pretty much what happens with the SuperCPU for the C64 as well, but the Tube really is a co-processor - there's something of a bottleneck in the design from what i understand, getting data back and forth to the external CPU is quite fiddly...? The Beeb is a pretty flexible beast though, i've seen a Master connected to a SID chip that simply runs C64 music code and then mirrors the registers into where the SID is mapped. =-) Not Atari but on a similar subject..i read a while back that Magnetic Scrolls who wrote adventure games like The Pawn and Guild of Thieves actually could use the processor in a Commodore 64 disk drive like a co-processor At some point I really must purge this trivia from my mind :-) Some demos used the drives cpu for processing stuff, not sure about games but it is possible. Pete Quote Link to comment Share on other sites More sharing options...
miker Posted September 2, 2009 Share Posted September 2, 2009 Can someone tell me why in all the huge space of the Internet is no rendition of "the blue danube" in MOD format available. Or , at least, a clean 3 channel SID to MOD converted track ... This site provides decent MIDI version of exactly what you mentioned. Wrathchild: Great job! Quote Link to comment Share on other sites More sharing options...
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