A report on Group coded recording

In computer science, group coded recording or group code recording (GCR) refers to several distinct but related encoding methods for representing data on magnetic media.

- Group coded recording

13 related topics with Alpha

Overall
Western Digital datasheet for the FD1771 floppy disk controller

Western Digital FD1771

0 links

First in a line of floppy disk controllers produced by Western Digital.

First in a line of floppy disk controllers produced by Western Digital.

Western Digital datasheet for the FD1771 floppy disk controller

The FD1781 was designed for double density, but required external modulation and demodulation circuitry, so it could support MFM, M2FM, GCR or other double-density encodings.

An octet code page 866 font table ordered by nibbles.

Nibble

0 links

Four-bit aggregation, or half an octet.

Four-bit aggregation, or half an octet.

An octet code page 866 font table ordered by nibbles.

In the Apple II microcomputer line, much of the disk drive control and group-coded recording was implemented in software.

Front view of the Commodore 4040 dual disk drive.

Commodore 4040

0 links

Replacement for the previous models 2040 and 3040 (Europe).

Replacement for the previous models 2040 and 3040 (Europe).

Front view of the Commodore 4040 dual disk drive.

The Group Coded Recording (GCR) scheme of binary encoding is used to store data on the magnetic disk medium.