diff --git a/README.md b/README.md
index 2137319..7c6a7b3 100644
--- a/README.md
+++ b/README.md
@@ -38,80 +38,6 @@ the minimum memory requirement may be less than 64k.
 |0x0003|1 byte   |may be used as iobyte by BIOS|
 |0x0000|3 bytes  |Jump to BIOS warm boot entry point / program exit|
 
-## BIOS Interface
-
-The entry points for the BIOS start at its base address.
-Each entry point is offset a multiple of 3 from the beginning of the BIOS.
-
-### BIOS+0 Boot
-
-The bootloader jumps here after loading the BIOS.
-
-### BIOS+3 Warm boot
-
-Reload the BDOS from disk, and call its entry point.
-The jump opcodes at the start of memory are re-initialized.
-
-### BIOS+6 Console status
-
-Checks if keyboard input is available.
-Returns FFh in AL (A) is character is available, 00 if not.
-
-### BIOS+9 Console read
-
-Read a character from keyboard from AL (A).
-This call does not return until a character is available.
-
-### BIOS+12 Console write
-
-Write character in DL (E) to the display.
-
-### BIOS+24 Seek disk to zero
-
-Seek current disk (selected with the following call) to its beginning.
-This is a commonly a no-op.
-
-### BIOS+27 Select disk
-
-Select disk by the number given in CL (C).
-
-This is equivalent to the DL number for the PC BIOS Int 13h.
-
-### BIOS+30 Set track
-
-Select track number for next disk i/o via register CX (BC).
-
-For CHS-adressed disks, the track number is the current cylinder multiplied by the number of heads plus the current head number.
-
-For disks with one side, the cylinder number is equal to the track number.
-
-### BIOS+33 Set disk sector
-
-Select sector on the current track in register CX (BC). This parameter is 1-based, this means the first sector is sector 1. The value 0 is invalid.
-
-For CHS-adressed floppies, the number of sectors per track might vary depending on the inserted floppy disk, even for the same drive.
-
-### BIOS+36 Set disk transfer address
-
-Set buffer for disk operations via register CX (BC).
-
-This is somewhat incompatible with CP/M versions since on modern systems, the sector size is 512 instead of 128 bytes.
-Setting it to the default value of 0x80 (which is the standard disk buffer for CP/M) will overwrite the first 0x180 bytes of the transient program area.
-
-The BDOS is expected to do deblocking to provide the application program with 128-byte disk i/o.
-
-### BIOS+39 Read sector
-
-Read sector previously specified.
-AL (A) is non-zero error code on failure.
-The error codes are implementation-specific.
-
-### BIOS+42 Write sector
-
-Write sector previously specified.
-AL (A) is non-zero error code on failure.
-The error codes are implementation-specific
-
 ## Application program interface
 
 It is using the `call 5` convention with CP/M compatible syscall numbers.