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YaPaDOS

1,094 bytes added, 22:47, 24 February 2012
/* Alpha version */
[[Image:Superdisk.gif|right]] YaPaDOS is patch for [[AMSDOS]] and [[ParaDOS]] that allows to redirect disk access to harddisk. This is done with keeping highest possible compatibility, so only 20 bytes of RAM are used (including 6 used by ParaDOS).
 
== What is this? ==
 
Not quite clear... Seems to be an AMSDOS clone from [[Yarek]] (?), for supporting his [[IDE8255]] (?) harddisk interface? Please confirm!
== Diskimages ==
Instead of reading and writting floppy, a continous and limited area on harddisk is used. The area has the same amount of sectors, as the floppy and is called diskimage. Each drive A: and B: separately can be directed to floppy or one of diskimages. You can change the diskimages as you would change the floppies, but by opening some special files.
Using only 20 bytes of RAM makes features like FAT32 and support for .DSK files impossible, so the disk must have special formatting using IDEDOS structures (defined by Garry Lancaster). The harddisk can also contain FAT partitions, but they are not accessible from YaPaDOS.
The IDEDOS partition contains diskimages, that can have various size (e.g. 180kB, 800kB, 5MB). Up to 999 diskimages can be created and accessed.
Diskimages are selected by their numbers 1..999 (0 means floppy) , by opening a file of special name. Only the number after dot matters. Names of diskimages can be listed from a virtual device called superdisk. Superdisk is read-only. After the superdisk is selected, the diskimage then can be selected without the '''^''' sign in file name.
== Commands ==
'''LOAD"^"''' - selects superdisk
'''LOAD"^.nnn"'''<BR>'''LOAD"^xxxxxxx.nnn"''' - selects diskimage number nnn(n - a digit, x - any character)
'''LOAD"^.0"''' - selects floppy
'''LOAD"^DESTROY.MBR"''' - clears MS-DOS partition table (also needs some POKEs for safety, see included README!.TXT)
'''LOAD"^DBnnnnn.mmm"''' - creates IDEDOS partition of nnnnn cylinders and up to mmm diskimages (needs some POKEs to set CHS geometry, see included README!.TXT)
'''LOAD"^MAKENEW"''' - adds diskimage respectively to current XDPB
All suggestions and ideas are welcome, please use the [http://groups.yahoo.com/group/futureos Yahoo! Groups list of FutureOS].
Download Alpha7 from: [http://cpc.yarek.com/amsdos2.zip http://cpc.yarek.com/amsdos2.zip] and please (version for SymbiFace IDE, plase contact to get other, e.g. CPCISA). Please backup all your harddisk data before use, as this version can include dangerous bugs. BTW it creates data structures <br> * Done since 2007-11-04:<BR>+ Special XDPB is set for superdisk XDPB.<BR>+ Diskimage sizes listed in superdisk.<BR>+ List floppy on superdisk.<BR>+ Support of IDE8255 (DSKHNDLR is written).<BR>+ LBA start is #000000 not #000001.<BR>+ Startup message with minor errors, so you would need name of DSKHNDLR.<BR>+ Redirection to delete them later anywayfloppy when wrong diskimage is selected.<brBR>+ Forbid disk creation from superdisk (has inadequate XDPB).<BR>+ Corrected XDPB of new diskimage (cylinders and sides).<BR>+ PARADOS |DRIVE tool installed in ROM bank 6 as |PRIVE.<BR>+ Size of floppy (diskimage ".000") is zero.<BR> * Done but not released:+ PARADOS |DRIVE tool installed in ROM bank 15 as |DRIVE.<BR>+ Formatting done on superdisk creates new diskimage (also from |DRIVE tool).<BR>+ Corrected free space printing in CAT to allow larger numbers.<BR>+ Better PARADOS |DRIVE tool synchronization.<BR> * To do is:<BR>- Rename diskimages from superdisk.<BR>- Support for Vortex 704 format.<BR>
* To do is:<br>- Support for Vortex 704 format.<br>* To fine tune is:<br>- Some bytes of XDPB of new diskimage.<brBR>- Recelculate amount of free space in sectors.<brBR>- Move the free space entry towards end of partition list.<br>- Correct message when wrong diskimage is selected.<brBR>- Test of diskimages placed over #0010000 LBA.<brBR>- Test of large diskimages (over 184 blocks).<brBR>- Selection Test of selection of diskimages number over 99.<brBR>- Listing Test of listing diskimages above number 99.<br>- Correct free space printing in CAT to allow larger numbers.<brBR>- Solve the "Broken in" error.<brBR>- Support for diskimages with sectors of 256B and 1kB.<brBR>- Correct support for Master/Slave.<brBR>- Installing PARADOS |DISC tool to other ROM bankIDE interface type detection (SF2, IDE8255, CPCISA).<BR>- Display real number of units after DSKHNDLR detection.<brBR>
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[[Category:Stub]] [[Category:Disc Operating_System]]
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