Flagon Bird

Use this forum to submit new files for the download section of the archive. I will check each submission and upload it to the archive on a regular basis.
prime
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Re: Flagon Bird

Post by prime »

Is the source available anywhere, including the auto-start loader, I'd like to try and work out why the CAS version is not working with DragonMMC's MTAPERUN?

Cheers.

Phill.
sixxie
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Re: Flagon Bird

Post by sixxie »

prime wrote:Is the source available anywhere, including the auto-start loader, I'd like to try and work out why the CAS version is not working with DragonMMC's MTAPERUN?
I did the loader and I don't think the CAS version does anything particularly special: it's basically just the output from bin2cas.pl. The autorun works by overwriting the next BASIC token pointer.

Code: Select all

bin2cas.pl  --autorun -o flagon.cas -n FLAGON --eof-data --dzip --fast \
        -B -l 0x0e00 screen.bin \
        --vdg 8 --sam-v 4 --sam-f 7 \
        -C --flasher main.bin
You can look at the Perl script to see what code is included for various options, but as you'll see, even though the content is zipped, the actual IO is all just calls to [BLKIN] as usual.

The WAV's a bit trickier and speeds up the loading by playing with pulse width counters (though I notice the version on the archive page is just a conversion of the CAS file, so doesn't include that fanciness).

Edit: how involved does DragonMMC get in the loading? One other slight deviation from normal is that the EOF block is allowed to contain data...
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robcfg
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Re: Flagon Bird

Post by robcfg »

I've seen that deviation in many games, so I assumed it's a legal practice.
sixxie
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Re: Flagon Bird

Post by sixxie »

Yeah perfectly acceptable to the normal load routines, just the ROM save calls don't make use of it. Well, probably not that then...
prime
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Re: Flagon Bird

Post by prime »

sixxie wrote:
prime wrote:Is the source available anywhere, including the auto-start loader, I'd like to try and work out why the CAS version is not working with DragonMMC's MTAPERUN?
I did the loader and I don't think the CAS version does anything particularly special: it's basically just the output from bin2cas.pl. The autorun works by overwriting the next BASIC token pointer.

You can look at the Perl script to see what code is included for various options, but as you'll see, even though the content is zipped, the actual IO is all just calls to [BLKIN] as usual.
Right I'll take a look at it, any idea why the loader it produces has it's exec address set outside the address range of the loader. Flagon seems to have a small normal file followed by a couple of headerless files.
The WAV's a bit trickier and speeds up the loading by playing with pulse width counters (though I notice the version on the archive page is just a conversion of the CAS file, so doesn't include that fanciness).

Edit: how involved does DragonMMC get in the loading? One other slight deviation from normal is that the EOF block is allowed to contain data...
The board has a 32K ram on it, into which it copies itself and the basic ROM and then patches the basic ROM at certain parts to read bytes from the mmc rather than from the tape. So most of the code is the normal Dragon (or CoCo) code I've just re-directedd things like byte in and byte out.

The odd things is I have four commands that are related to this :
MCAS which does the copying to RAM & patching
MMOUNTR "filename.cas" which sets the file to input from
the CLOAD / CLOADM to load the actual file.

Doing the load with MCAS:MMOUTR"flagon.cas":CLOADM works as if from tape and the game starts.

MTAPERUN "flagon.cas" tries to do all three, it does also however also check the tape file type so that it can run a basic program and exec a machine code, after reseting the basic stack and clearing to 200 bytes of strings space as this is the environment a lot of the comercial games expect.

Cheers.

Phill.
sixxie
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Re: Flagon Bird

Post by sixxie »

prime wrote: Right I'll take a look at it, any idea why the loader it produces has it's exec address set outside the address range of the loader. Flagon seems to have a small normal file followed by a couple of headerless files.
The autorun code is just another variation on the old themes. All the loader code is in the header block, the data block for the first part patches the BASIC "next token" sequence to a) point BASIC at a ':' character so that BASIC does another token fetch, and then b) JMP to the loader code (instead of actually do the token fetch).

As such the EXEC address isn't used by BASIC, and I actually just use that field to keep the ':' character.
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Bosco
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Re: Flagon Bird

Post by Bosco »

Hi Prime.

I've sent you a PM.
Shock Trooper
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Re: Flagon Bird

Post by Shock Trooper »

Hello,

Can you release a cassette to purchase with Microdeal / Dragon Data style inlay card (like Dunjunz) for this game, thanks.

Are there any other new release Dragon games with cassette & inlay card like Dunjunz? Thanks again.
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Bosco
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Re: Flagon Bird

Post by Bosco »

Hi Shock Trooper.

Thanks for the suggestion. I managed to bag myself a Dunjunz cassette last Cambridge meet-up from Sixxie himself.

I have to say Sixxie did a great job and it did make me think about producing a limited run of my games on cassette and cartridge.

I'm planning to update Flagon Bird so a cassette release might be more appropriate once that's done.

With regard to other recent Dragon titles on cassette I don't know of any. I have an original game currently in the works targeting John Linville's GMC cartridge but that's a little way off yet. I imagine at some point it'll make it over to cassette albeit minus enhanced audio. https://youtu.be/s1MAAD5dtqo

Sorchard also has a game in development, but I couldn't comment on it's status. Here's a link to his blog though. http://returnofthebeast.blogspot.com/20 ... otabb.html
Alastair
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Re: Flagon Bird

Post by Alastair »

Shock Trooper wrote:Are there any other new release Dragon games with cassette & inlay card like Dunjunz? Thanks again.
Whilst it is not exactly new as it was released in 2007 (I can't believe it was that long ago) Cronosoft still has some copies of James McKay's Glove available.
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