125
Checkpoint Code | Description | 
  | 
  | 
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 shadowing. 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.  | 
  | 
  |