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PPcenter. Arts and craft for my Sega Saturn. Since 1847 :D

Iso/Cue "loader" works on real hardware :]

Written by cafealpha no comments
(For more informations, you can also read this old article.)

I finally had time to use my Saturn, and I could verify that iso/cue "loader" works on real hardware !
Of course it works well when reading from RomFs, and it works also well when reading file from SD card

data/images/20150626_iso_loader.tb.jpg
My test environment ... sorry for the mess
(Micro SD card is located on top-left of the cartridge)

I lost some time to understand why data transfer from SD card was slower than expected, but finally understand why : some debug/whatever delay routine was called when accessing cartridge registers ...
Just putting some #if 0 around this delay code solved the "problem" ^^;

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Iso/Cue "loader" works :)

Written by cafealpha no comments
So I am making an enhanced version of Pseudo Saturn firmware.
And, as an extra feature of this firmware, I added an iso/cue "loader".
data/images/20150603_dr.evil.laser2.tb.jpg

Why the quotes around "loader" ? Because it doesn't emulates CD-block
So, it only loads few homebrew games, but it's enough for me, and I don't want to waste more time on adding CD block software emulator while better solutions (rhea, jhl's "mpeg" cart, etc) already exist.

As an other bonus, I also added RomFs support to my Saturn library
It is like romdiskfs that is widely used on linux, DS homebrew, etc, but it allows file compression, some other features, and ... is probably buggy because I coded it from scratch

(*) Virtual file system is not really new on Saturn homebrew scene, because Piratero already implemented one in libyaul a while ago


data/images/20150603_romfs_filelist.png
RomFs root folder contents. I will load sl_elf.iso file in the next paragraph.

So here is a capture of yabause running sl_elf.iso, after decompressing it from virtual file system stored in Flash memory.
sl_elf.iso is "satdemo" made by CharlesDoty, grabbed from SaturnOrbit's examples (Thank you Rockin'B for making SaturnOrbit ! After 10 years, it still have it installed on my laptop's hard disk ).

data/images/20150603_isocueloader.png
yabause running Saturn demo from iso file, near SatLink software I use in order to debug my Saturn programs.

Very big thanks to the yabause team ! I grabbed the iso/cue loading routines from yabause sources, and it was very easy to port them

Edit : I removed unused code (CD Block emulation routines, etc) from iso loader module, and .o size dropped from 74KB to 18KB oO

Edit (2015/06/26) : I tested this code on real hardware, and it works too ! Please see this article for more details.

Read more Iso/Cue "loader" works :)

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