0/1 RF0
100000 - error
040000 - freeze
020000 - write check error
010000 - data parity error
004000 - non-existent disk
002000 - write lock out
001000 - missed transfer
000400 - disk clear
000200 - control ready
000100 - interrupt enable
000040 - extend memory
000020 - extend memory
000010 - maintenance
000004 - function
000002 - function
000001 - go

1/n - RKn
100000 - drive error
040000 - overrun
020000 - write violation
010000 - seek error
004000 - programming error
002000 - non-existent memory
001000 - data late
000400 - timing error
000200 - non-existent disk
000100 - non-existent cylinder
000040 - non-existent sector
000020 -
000010 -
000004 -
000002 - checksum error
000001 - write check error

2/n TCn
100000 - end zone
040000 - parity error
020000 - mark track error
010000 - illegal operation
004000 - selection error
002000 - block missed
001000 - data missed
000400 - non-existent memory
000200 - tape is up to speed
000100 - clock simulates timing
000040 - maintenance mark track
000020 - data track
000010 - data track
000004 - data track
000002 - extended data
000001 - extended data

3/n MTn - no messages

4/n RPn
100000 - write protect violation
040000 - file unsafe violation
020000 - non-existent cylinder
010000 - non-existent track
004000 - non-existent sector
002000 - program error
001000 - format error
000400 - mode error
000200 - longitudinal parity error
000100 - word parity error
000040 - checksum error
000020 - timing error
000010 - write check error
000004 - non-existent memory
000002 - end of pack
000001 - disk error