| Appendix B: AMIBIOS POST Codes  | 
  | 
  | 
Checkpoint | Code Description  | 
48h | Patterns written in base memory. Determining the amount of memory  | 
  | below 1 MB next.  | 
49h  | The amount of memory below 1 MB has been found and verified.  | 
  | Determining the amount of memory above 1 MB memory next.  | 
4Bh  | The amount of memory above 1 MB has been found and verified.  | 
  | Checking for a soft reset and clearing the memory below 1 MB for  | 
  | the soft reset next. If this is a power on situation, going to checkpoint  | 
  | 4Eh next.  | 
4Ch  | The memory below 1 MB has been cleared via a soft reset. Clearing  | 
  | the memory above 1 MB next.  | 
4Dh  | The memory above 1 MB has been cleared via a soft reset. Saving  | 
  | the memory size next. Going to checkpoint 52h next.  | 
4Eh  | The memory test started, but not as the result of a soft reset.  | 
  | Displaying the first 64 KB memory size next.  | 
4Fh  | The memory size display has started. The display is updated during  | 
  | the memory test. Performing the sequential and random memory test  | 
  | next.  | 
50h  | The memory below 1 MB has been tested and initialized. Adjusting  | 
  | the displayed memory size for relocation and shadowing next.  | 
51h  | The memory size display was adjusted for relocation and shadow-  | 
  | ing.  | 
  | Testing the memory above 1 MB next.  | 
52h  | The memory above 1 MB has been tested and initialized. Saving  | 
  | the memory size information next.  | 
53h  | The memory size information and the CPU registers are saved.  | 
  | Entering real mode next.  | 
54h  | Shutdown was successful. The CPU is in real mode. Disabling the  | 
  | Gate A20 line, parity, and the NMI next.  | 
57h  | The A20 address line, parity, and the NMI are disabled. Adjusting  | 
  | the memory size depending on relocation and shadowing next.  | 
58h  | The memory size was adjusted for relocation and shadowing.  | 
  | Clearing the Hit <DEL> message next.  | 
59h  | The Hit <DEL> message is cleared. The <WAIT...> message is  | 
  | displayed. Starting the DMA and interrupt controller test next.  |