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 Ramdisk if detectedselected.* Ramdisk is chosen with drive 'C' or 'D'using |DRIVE only. The XDPB for the ramdisk is fixed and canisn't be auto detected. In addition data within the XDPB is used to identify Ramdisk 'formats'. 'Auto select' parameter is 1 for a ramdisk based format, which has a dual purpose of identifying it and preventing auto-detection and the filler byte 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 discs so that BASDOS format can be used.* Drive 'A' or 'B' can be DATA, BASDOS format (704KB) or SYSTEM/VENDOR. IBM format is replaced by BASDOSformat.
* 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 for it within the BASDOS ROM.* BASDOS can boot both [[MicroDOS]] and Amstrad CP/M based using |CPM depending on the detected disc format. Read id is used to detect which is used. Both the sector ID (R) and sector size (N) from the read id results are used. A ram expansion is required for MicroDOS. Both BASDOS and MicroDOS should be useable on a CPC.
[[Category:Stub]] [[Category:Disc Operating_System]]