On the original ROMs (128k, 512k, 512ke, Plus):Die Sad Mac Codes (bis MacPlus)
Dieser Text ist im Internet als File sad-mac-codes.hqx abgelegt
On the original ROMs (128k, 512k, 512ke, Plus):
When you press the interrupt button on the side of your Macintosh when booting, you should get a sad Mac icon with '0F000D' and some bits cycling under the icon indicating it is performing a memory test.
This numeric code is in two parts: the first two characters are the class code and the second four are the sub code. The class code tells what part of the diagnostic program found the error and the sub class code tells what the error was. In the case of a bad RAM chip, the sub class identifies the bad chip (this was very helpful to homegrown upgraders).
| Class Code | Sub Code |
|---|---|
| 1 = ROM test failed | Meaningless |
| 2 = Memory test - bus subtest | identifies bad chips |
| 3 = Memory test - byte write | identifies bad chips |
| 4 = Memory test - Mod3 test | identifies bad chips |
| 5 = Memory test - address uniqueness | identifies bad chips |
| Data Bit | Location | Sub Code Bits |
|---|---|---|
| 0 | F5 | 0001 |
| 1 | F6 | 0002 |
| 2 | F7 | 0004 |
| 3 | F8 | 0008 |
| 4 | F9 | 0010 |
| 5 | F10 | 0020 |
| 6 | F11 | 0040 |
| 7 | F12 | 0080 |
| 8 | G5 | 0100 |
| 9 | G6 | 0200 |
| 10 | G7 | 0400 |
| 11 | G8 | 0800 |
| 12 | G9 | 1000 |
| 13 | G10 | 2000 |
| 14 | G11 | 4000 |
| 15 | G12 | 8000 |
| Class Code | Sub Code |
|---|---|
| F = Exception | 0001 Bus error |
| 0002 | Address error |
| 0003 | Illegal instruction |
| 0004 | Zero divide |
| 0005 | Check instruction |
| 0006 | Traps instruction |
| 0007 | Privilege violation |
| 0008 | Trace |
| 0009 | Line 1010 |
| 000A | Line 1111 |
| 000B | Other exception |
| 000C | Nothing |
| 000D | NMI (normal indication) |
| 0064 | Couldn't Read System File into Memory |