1.6
Bus Phases
The SCSI bus must be in one of the following eight phases:
•
BUS FREE phase
•
ARBITRATION phase
•
SELECTION phase
•
RESELECTION phase
•
COMMAND phase
•
DATA phase
•
STATUS phase
•
MESSAGE phase
The SCSI bus can never be in more than one phase at any given time.
Note:
In the following bus phase conditions, signals are false unless otherwise defined. Signals on
the timing charts are assumed to be positive logic (or active high).
C141-C011
INFORMATION TRANSFER phase
1-47