Bitshifter's Z-code interpreter

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Bit Shifter
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Re: Bitshifter's Z-code interpreter

Post by Bit Shifter »

Mike wrote:
Bit Shifter wrote:You need a VIC (or an emulator setting) with 40K !
32K is not enough, there must also be RAM in the block 5 ($A000-$BFFF).
"+32K" is commonly referred to as the RAM configuration with RAM in BLK1..3 and BLK5.

If you also use the 3K in the address range $0400..$0FFF (like Kweepa did with VIC Doom or I did here), you'll often have to stress this out though: many people otherwise just ignore this or don't take this serious (like in: "but doesn't just +32K suffice?") and then wonder the program/tool/game doesn't run with "just +32K".

Those "+35K" (or "+32K +3K") are also the biggest common denominator, as this is the maximum RAM you can get on the VIC-20, if you:

- remain at an unbanked RAM setup (there is no agreed upon or at least wide-spread enough standard for banked RAM!), and
- leave the I/O area for its intended purpose, i.e. as I/O registers or other resource, strictly for the use by the cartridge firmware only!

+32K +3K is supported by Mega-Cart, FE3 and Ultimem. In case of FE3 though, due to issues with the CPLD firmware (*not* the FE3 menu firmware!), crosstalk between RAMx and BLKx can happen - mainly on NTSC VIC-20s, but this has also been reported on some PAL VIC-20s - rendering the +32K +3K configuration problematic for FE3 users. :(
Mike,
thanks for the clarification.
My interpreter needs the +35K configuration, the one, you described above.
Even then it wasn't easy to put a highres bitmap, a font, the resident part of an Infocom story, a disk cache and the program itself into this amount of RAM. Normally Z interpreters run comfortably on machines with 48K RAM or more and then in text mode only.
The side effect is, that the disk cache is too tiny. Even simple commands like "inventory" or "look" access 10-20 different story pages (disk blocks of 256 bytes) and if the disk cache cannot store that many pages it loads them all for each command! Running the program on a real VIC-20 with a real 1541 can be painfully slow. I recommend an emulator with warp-mode or at least an accelerated disk access (JiffyDOS or others).
Bit Shifter
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Mike
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Re: Bitshifter's Z-code interpreter

Post by Mike »

Bit Shifter wrote:My interpreter needs the +35K configuration, the one, you described above.
:shock: ... O.K., then: Welcome to the Club (of the "+35K" programmers)! :mrgreen:
Running the program on a real VIC-20 with a real 1541 can be painfully slow. I recommend an emulator with warp-mode or at least an accelerated disk access (JiffyDOS or others).
In VICE, turning TDE (True Drive Emulation) off and using VDrive instead is the better option. Direct sector access also works in VDrive. Warp Mode (or max. speed no limit) just messes up the perceived timing and all SFX/music becomes unrecognisable.
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Re: Bitshifter's Z-code interpreter

Post by Kweepa »

The font looks great on a real VIC!
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Re: Bitshifter's Z-code interpreter

Post by Bit Shifter »

I looked, wether I could spare the 3K memory range of $0400-$0FFF, but that would cut the disk cache section into half the size and make it too tiny to be useful. So I left the memory layout as it is, hoping that the +35K memory requirement is not too restrictive.
Here's now the new version of the ZORK trilogy and I hope, that it's near to the final release. :D
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Mike
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Re: Bitshifter's Z-code interpreter

Post by Mike »

Bit Shifter wrote:[...] I left the memory layout as it is, hoping that the +35K memory requirement is not too restrictive.
Not any more 'restrictive' today than it has been for all the time anyhow.

The +35K RAM expansion is fully supported by the VIC-20 hardware. As long as we stick to this setup - if RAM expanders provide these +35K, they all provide them exactly the same way, at the same address ranges, without any necessary banking. Couldn't be any better off for a standard. Of course, when a program is content with less memory or strictly depends on certain positions for BASIC start and screen RAM position (as with unexpanded or +3K versus +8K or more), it should be clearly stated in its description.
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Re: Bitshifter's Z-code interpreter

Post by Mike »

I split the hardware issues of ral-clan's setup into an own thread in the Hardware section:

RAM expansion cross-talk issues (split from: Bitshifter's Z-code interpreter)
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Re: Bitshifter's Z-code interpreter

Post by orion70 »

So guys, what's going on in the Zork land? Have the tester(s) tested the games thoroughly? Is there any final release of the Trilogy? What about the other Infocom adventures? Thank you Bit Shifter for your contribution, the opportunity to save games is invaluable.
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Re: Bitshifter's Z-code interpreter

Post by orion70 »

Bumpity bump! No one?
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Re: Bitshifter's Z-code interpreter

Post by Bit Shifter »

I had no feedback during the last two months, so I think I should release the current version of the interpreter.
Together with some story files, the Zork trilogy, and then Deadline, Suspect and Witness.
I'll do some final tests before.
まで来週
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Re: Bitshifter's Z-code interpreter

Post by orion70 »

Great choice of titles! :D Planetfall would also make a good one. Thanks again for your effort.
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Re: Bitshifter's Z-code interpreter

Post by Bit Shifter »

Here's now the (first :wink: ) final release of my Z interpreter together with the Zork trilogy as example stories.
Have fun with these famous adventures of the previous millenium. :D
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Re: Bitshifter's Z-code interpreter

Post by orion70 »

Downloaded one time :)
Thanks a lot!
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Bit Shifter
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Re: Bitshifter's Z-code interpreter

Post by Bit Shifter »

And here is another trilogy with the stories "deadline", "suspect" and "witness" ...
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Re: Bitshifter's Z-code interpreter

Post by ral-clan »

Thanks very much for creating this port!
Image Music I've made with 1980s electronics, synths and other retro-instruments: http://theovoids.bandcamp.com
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Re: Bitshifter's Z-code interpreter

Post by Bit Shifter »

orion70 wrote:Great choice of titles! :D Planetfall would also make a good one. Thanks again for your effort.
Your wish is my command :wink: Here is "planetfall" and the sequel "stationfall".
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fall.zip
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