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70
Additional Bus Checkpoints
While control is in the bus routines, additional checkpoints are ouput to I/O
port address 0080h as word to identify the routines being executed. These are
word checkpoints. The low byte of checkpoint is the system BIOS checkpoint
where control is passed to the different bus routines. The high byte of
checkpoint indicates that the routine is being executed in different buses.
The high byte of these checkpoints includes the following information:
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Chapter 4
System Resources
