archive.worldofdragon.org

So I have an (old inlay style) tape of Dragon Invaders, but it blatantly doesn't work. It also doesn't match up to any of the copies in the archive.

Same both sides, seems to be two copies which, reading the hex dumps, probably just changes the graphics mode. But neither actually work. Everything about the inlay and tape looks authentic, and they load cleanly, they just crash

Not looking to try and actually get these to work - it's not exactly a great game - just wondering if anyone else had seen this? I can't vouch for the provenance of my tape - it probably came with an ebay purchase years ago - so it is possible someone overwrote it with bad data. Attached a cas copy in case anyone's interested.

Do you have a wave dump I can take a look?

robcfg wrote: ↑Tue Jan 24, 2023 9:40 pm Do you have a wave dump I can take a look?

Sure: http://www.6809.org.uk/tmp/da/cassettes ... vaders.wav

It's really strange...

Both copies of the game on the CAS file are identical but for one byte (and the CRC) on the 2nd data block.

On the 1st copy it's 0xE8 and on the 2nd one it's 0xF8. The CRCs match on both copies.

Both the original CoCo game and the version we already have archived do work on XRoar, but not this one...

Yeah - as I say, I think that one byte is probably just the graphics mode based on context. Multiple copies in different graphics modes seemed to be the way things were done early on.

But it's totally non-working! So I'd really love to know if anyone else has encountered this - if not, I'm willing to accept the theory that a previous owner just wrote bad versions to the tape.

The first mention I can find in Dragon User was in October 1983 where John Scriven (deservedly) gave it a nice sarcastic sentence or two. But he didn't mention having to return it for a better copy

If a previous owner had saved it to the tape could they have used the wrong CSAVEM values?