[Coco] 2 Sides in VCC

[Luis Fernández]

Curiously in the VCC is can create virtual disks of 2 faces, and 80 track, although only be formatted 35 track and 1 Sided
I have 2 questions
1) when we create 2 Sided the VCC adds 2 bytes at beginning of disk, with & h12 y & h02, of course are 18 sectors per track and two sides. when one side is selected, adds nothing.
I wonder if this method is standard or VCC is somewhat unique, in other words, it uses some other emulator, or a disc burning utility real? someone uses this header 2 bytes?
2) even if the disc do 80 track (written with zeros) Vcc always formatted only 35 tracks 18 sectors per track (filled with 255), and when both sides are jumping the track 36 sectors, this is logical as this represent both sides in other virtual disks,
Now,
What is the impediment to the DECB can use 80 track and / or 2-sided
Let's see: 80 track physically need the appropriate controller and drive 5 1/4 or 3 1/2 right. DECB level but I see no impediment, would track 80 - 1 for directory => 79 * 2 = 158 clusters, with the dir in the track 17, the fat would not have disabilities and you can use up to 191 cluster smoothly, with regarding dir entries (currently 9 sectors * 256/32 = 72 entries), this is easily expandable to 14 * 256/32 = 112, or twice if you use only 16 bytes per entry, but let in 112 for compatibility
I mean this in no nitros DECB, the basic internal buffers if would not be sufficient.
In some emulators are used drive 0 = Side A and Side B = Drive1 when are two sides, and 36 sectors per track, I have some confusion in all this
I think the controller J-DOS can handle disks of 80 track and need a DOS different
But the truth not seen him impediment of that DECB or RGBDOS or HDB-DOS maintain 80 track
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Excuse my English, I use google translator, my language is Spanish, I'm Spanish but I live in Venezuela
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