One of the most cryptic and perplexing issues with any computer is the strange codes that are displayed on the monitor when a fault or error is encountered by the system. Most of these codes are just a mix of numbers amd letters with no meaning to the ordinary user. Much of the time these codes spell disaster but all is not lost as below is a summary of many of these error codes and what they mean. Even with this list some of the codes still remain obscure but at least it will give you a starting place to look for the problem encountered.
Floppy Disk Boot-up
| X |
01 |
No Sync pulse detected |
| X |
02 |
No Header |
| X |
03 |
Header checksum error |
| X |
04 |
Incorrect track |
| X |
05 |
Incorrect sector |
| X |
06 |
Not a data block |
| X |
07 |
Data checksum error |
| X |
08 |
Sync too long |
| X |
99 |
Not a system disk |
Hard Disk Boot-up
| X |
81 |
No index detected |
| X |
82 |
Complete signal not detected |
| X |
83 |
Write fault |
| X |
84 |
Drive not ready |
| X |
86 |
Track 00 not found |
| X |
90 |
ID field error |
| X |
91 |
Uncorrectable error |
| X |
92 |
Address mark not found |
| X |
94 |
Incorrect sector |
| X |
95 |
Seek error |
| X |
98 |
Correctable data error (no system ?) |
| X |
99 |
Bad track |
Floppy System Error Codes
| 11 |
Noise on Sync |
Read errors |
| 12 |
Bad ID - header |
|
| 13 |
Header checksum error |
|
| 14 |
Header GCR error |
|
| 15 |
Wrong track |
|
| 16 |
Wrong sector |
|
| |
|
|
| 21 |
Bad ID - data |
Invalid data |
| 22 |
Checksum error - data |
|
| 23 |
GCR error - data |
|
| 24 |
Sync timeout |
|
| |
|
|
| 31 |
Bad ID - data |
Drive/Disk defect |
| 32 |
Verify error |
|
| 33 |
Checksum error |
|
| 34 |
GCR error |
|
| |
|
|
| 41 |
No sync found |
Format errors |
| 42 |
Bad ID - header |
|
| 43 |
Wrong track |
|
| 44 |
Wrong sector |
|
| 45 |
Checksum error - header |
|
| 46 |
Gap error |
|
| 47 |
GCR error |
|
| 48 |
No data sync |
|
| 49 |
Bad ID - data |
|
| 4A |
Verify error - data |
|
| 4B |
Checksum error - data |
|
| 4C |
Gap 2 error |
|
| 4D |
GCR error |
|
| |
|
|
| F1 |
Double sided disk (single sided system) |
Miscellaneous errors |
| F3 |
Cannot write data - disk changed |
|
| F4 |
Cannot write until disk logged |
|
| F5 |
Wrong operating system type data (CP/M / MS-DOS) |
|
| F6 |
Cannot start disk operation |
|
| F7 |
Illegal track number |
|
| F8 |
Illegal drive number |
|
| F8 |
Illegal operation |
|
| FA |
Disk drive door open |
|
| FB |
Motor not at speed (disk "sticking" ? |
|
| FC |
Write protected disk |
|
| FD |
Bad track |
|
| FE |
Cannot complete operation |
|
| FF |
No sync (bad or unformatted disk) |
|
Hard Disk System Error Codes
| 00 |
No Error |
| 01 |
No index detected |
| 02 |
Seek not complete |
| 03 |
Write fault |
| 04 |
Drive not ready |
| 06 |
Track 00 not found |
| |
|
|
| 10 |
ID field error |
| 11 |
Uncorrectable data error |
| 12 |
Address mark not found |
| 14 |
Sector not found |
| 15 |
Seek error |
| 18 |
Correctable data error |
| 19 |
Bad track |
| |
|
|
| 1A |
Format error |
| |
|
|
| 20 |
Invallid command |
| 21 |
Illegal disk command |
| |
|
|
| 30 |
Controller RAM failure |
| 31 |
Controller PROM failure |
| 32 |
ECC diagnostic failure |
The list above is not a difinative list but it does hint at the most common error codes encountered.