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/* BASDOS */
'''BASDOS''' (BASIC Disc Operating System) is a patched AMSDOS made in East Germany (GDR) for the [[KC Compact]].
The disc interface for the KC Compact contains the BASDOS rom, a NEC765 disc controller and 64KB RAM.
Differences compared to AMSDOS:
* There is a new block of code at &dc00-&df00 in the ROM which starts with a small jumpblock. This code implements the patches. Other parts of the ROM have been patched to call into this.
* Disc motor handler is patched to support a Ramdiskif detected. It uses * Ramdisk is chosen with drive 'C' or 'D'. The XDPB is fixed and can't be auto detected. In addition data within the XDPB is used to determine if itidentify Ramdisk 'formats's a disc based or ram based CPM based disc format. (auto 'Auto select ' parameter is 1 for a ramdisk based format with , which has a dual purpose of identifying it and preventing auto-detection and the filler byte parameter defining has been repurposed to define the base ram page of the ramdisk). The ramdisk uses KC Compact RAM Expansion/Amstrad compatible RAM Expansions.* Read/write is patched to allow double sided discsso that BASDOS can be used.
* Drive 'A' or 'B' can be DATA, BASDOS format (704KB) or SYSTEM/VENDOR. IBM is replaced by BASDOS.
* Drive 'C' accesses a 64KB RAM DISK. (1KB blocks, 64 blocks, 32 directory entries). Uses second bank with ram selections from c4.
* Drive 'D' accesses a 192KB RAM DISK. (2KB blocks, 96 blocks, 128 directory entries). Uses second bank with ram selections from e8. Useful if you have a 256KB/512KB ram expansion.
* the double sided [[MicroDOS]] disc format is only supported in Microdos and not in AMSDOS mode. There are no XDPB which have sector size N=3 defined in the ROM.* can boot both [[MicroDOS]] and Amstrad CP/M based on the detected disc format. Read id is used to detect which is used. Both the sector ID and sector size are used. A ram expansion is required for MicroDOS.
[[Category:Stub]] [[Category:Disc Operating_System]]
