CPCs could read discs formatted in three separate ways. Several high-capacity disc operating systems existed to add new formats to the three standard ones.
Standard CPC disc formats
- Data: 180k single-sided. 40 tracks of nine 512-byte sectors each. Sectors numbered &C1 to &C9. 64 directory entries. Can also be read by PCWs. The useable capacity is 178k.
- System: 180k single-sided. 40 tracks of nine 512-byte sectors each. Sectors numbered &41 to &49. 64 directory entries. Two reserved tracks containing CP/M BIOS. The useable capacity is 169k.
- IBM: 160k single-sided. 40 tracks of eight 512-byte sectors each. Sectors numbered &01 to &08. Provided for compatibility with CP/M-86 (?). The useable capacity is 158k.
- Vendor: Term used for System format discs with no software in the reserved tracks. The useable capacity is 169k.