Diagnostic Rom: wrong image size

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Rolo
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Diagnostic Rom: wrong image size

Post by Rolo »

The image of "Dragon Data Ltd - Diagnostic Rom.ROM" of the download section has a size of 8193 bytes (8k plus 1).The last significant byte is at $0600. $0601 to $2000 is made up of $FF and $B4 (and a final $10). In reality, it's just a 4k cartridge. I simply cut off the last byte for my multi-cart.
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tormod
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Re: Diagnostic Rom: wrong image size

Post by tormod »

I had a look too. From 0x600 up to 4k it is all FF which is unused ROM. From 4k to 8k it is all B4 which I guess is reading from nowhere. The 0x10 at 8k is probably a wrap-around to address 0 which also has 0x10 - the cartridge ROM is 4k, its address decoding is 8k, but the CTS* line enables it on the whole 16k space.
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Rolo
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Re: Diagnostic Rom: wrong image size

Post by Rolo »

Yes, obviously it is a 4k cartridge. The rest of the file is garbage.
For my multi-cart however I need 8k images.
jedie
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Re: Diagnostic Rom: wrong image size

Post by jedie »

I saw the Diagnostic Rom (1982)(Dragon Data Ltd)[!].ROM here: https://archive.worldofdragon.org/brows ... stic%20Rom

But didn't find information about this. No search results in Wiki: https://archive.worldofdragon.org/index ... fulltext=1

This Thread is the only one with some information.
... too many ideas and too little time ... Related stuff written in Python:
Dragon 32 emulator / PyDC - Python Dragon 32 converter: https://github.com/jedie/DragonPy
DWLOAD server / Dragon-Lib and other stuff: https://github.com/6809
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