
User’s Manual
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 | 4B | The amount of memory above 1MB has been found and verified. | 
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 | Checking for a soft reset and clearing the memory below 1MB for the | 
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 | soft reset next. | 
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 | If this is a power on situation, going to checkpoint 4Eh next. | 
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 | 4C | The memory below 1MB has been cleared via a soft reset. Clearing | 
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 | the memory above 1MB next. | 
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 | 4D | The memory above 1MB has been cleared via soft reset. Saving the | 
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 | memory size next. Going to checkpoint 52h next. | 
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 | 4E | The memory test started, but not as the result of a soft reset. | 
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 | Displaying the first 64KB memory size next. | 
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 | 4F | Memory size display started. This will be updated during memory test. | 
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 | Performing the sequential and random memory test next. | 
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 | 50 | Memory testing/initialization below 1MB completed. Going to adjust | 
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 | displayed memory size for relocation and shadowing. | 
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 | 51 | The memory size display was adjusted for relocation and shadowing. | 
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 | Testing the memory above 1MB next. | 
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 | 52 | The memory above 1MB has been tested and initialized. Saving the | 
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 | memory size information next. | 
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 | 53 | The memory size information and the CPU registers are saved. | 
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 | Entering real mode next. | 
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 | 54 | Shutdown was successful. The CPU is in real mode. Disabling the | 
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 | Gate A20 line, parity, and the NMI next. | 
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 | 57 | The A20 address line, parity, and the NMI are disabled. Adjusting the | 
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 | memory sizedepending on relocation and shadowing next. | 
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 | 58 | The memory size was adjusted for relocation and shadowing. Clearing | 
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 | the Hit <DEL> message next. | 
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 | 59 | The Hit <DEL> message is cleared. The <WAIT…> message is | 
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 | displayed. Staring the DMA and interrupt controller test next. | 
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 | 60 | The DMA page register test passed. To do DMA#1 base register test. | 
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 | 62 | DMA#1 base register test passed. To do DMA#2 base register test. | 
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 | 65 | DMA#2 base register test passed. To program DMA unit 1 and 2. | 
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 | 66 | DMA unit 1 and 2 programming over. To initialize 8259 interrupt | 
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 | controller. | 
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 | 7F | Extended NMI sources enabling is in progress. | 
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 | 80 | The keyboard test has started. Clearing the output buffer and checking | 
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 | for stuck keys. Issuing the keyboard reset command next. | 
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100
