Changes
An exception are the Vortex F1-S, F1-D, M1-S and M1-D drives. (How are they different?)
== Unconnected pins ==
At the end of a successful read or write command, the program should send a ''Terminal Count'' (TC) signal to the FDC. However, in the CPC the TC pin isn't connected to the I/O bus, making it impossible for the program to confirm a correct operation. For that reason, the FDC will assume that the command has failed, and it'll return both Bit 6 in Status Register 0 and Bit 7 in Status Register 1 set. The program should ignore this error message.
The CPC doesn't support floppy DMA transfers, and the FDC's Interrupt signal isn't used in the CPC.
In the CPC the DS1 signal of the FDC is not connected, making it impossible to select floppy drives 2 and 3. The floppy drives 0 and 1 are selected instead.
== Notes ==
Despite the name, a sector with a ''Deleted data Address Mark'' (DAM) is not deleted; the DAM-flag is just another ID bit. 'Deleted' sectors can be read/written just like normal data sectors and if that ID bit is specified correctly in the command.
Usually single sided 40-track 3" disk drives are used in CPCs. For practical purposes, 42 tracks could be used — the limit is specific to the drive and some support more tracks but 42 is a good maximum. The FDC controller can be used to control 80-tracks and/or double sided drives, though AMSDOS doesn't support such formats. AMSDOS supports a maximum of two disk drives only.
