At 09:58 AM 3/10/99 -0300, you wrote:
>That's ok for Konami, Compile and T&E Soft games, but there are some
>strange ones that does use other ways of block switching. BTW, T&E does
>use very often LD HL,0302h / LD (9FFFh),HL
Hmmm, ROMs like that would be difficult to adapt for ESE-SCC.
MegaRAM does allow such a page switch, right?
>I had saw in Nemesis x, F1 Spirit and Penguin Adventure that Konami, at
>each interrupt, changes blocks 1, 2 and 3 to 13, 14 and 15, respectively
>at positions 6000h, 8000h and A000h.
A crack could group blocks like this: 0 and 1, 2 and 3, 0 and 13, 14 and
15. 8K is "lost" because block 0 is duplicated. But switching is very
efficient: two blocks can be switched using a single OUT to the mapper.
Ofcouse blocks visited as frequently as these were never put in VRAM.
>I didn't know that the DSK version was adapted to run with only 256kb of
>Memory Mapper! What was more difficult: translate do English or adapt do
>256kb of Mapper?
I can't say, because it was not me but Martos who did the 256K version. The
only thing I did to it was fix a bug in the load routines. Before the bug
was fixed the 256K version crashed quite often.
The 256K version is without sound however, so it is not equal to the 512K
version.
>But, with direct access to FDC, the data transfer rate is maximized. And
>the main idea was copy protection, using special formatting (1kb sectors)!
Why use copy protection on cracked games? Isn't the whole point of a
cracked game that you don't have to buy it?
By the way, 1K sectors can be loaded by some diskROMs. 8250 can do it,
turbo R can't. I was planning to use it as a copy protection as well. But
because I didn't want to do direct FDC access, I discarded it.
Bye,
Maarten
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