Datasheet

18-32 MCF5407 User’s Manual
General Operation of External Master Transfers
Figure 18-32. Three-Wire Bus Arbitration Protocol State Diagram
Table 18-11 lists conditions that cause state transitions.
Table 18-11. Three-Wire Bus Arbitration Protocol Transition Conditions
Current
State
Condition
Label
RSTI
Software
Watchdog
Reset
BG
Bus
Request
Transfer
in
Progress
End of
Cycle
1
Next State
Reset A1 Asserted —————Reset
A2 Negated Asserted ————Reset
A3 Negated Negated Negated ———EM
A4 Negated Negated Asserted ———Implicit
master
Implicit
master
B1 Negated Negated Negated ———External
device
master
B2 Negated Negated Asserted ———Explicit
master
B3 Negated Negated Asserted Negated ——Implicit
master
B4 Negated Negated Asserted Asserted ——Explicit
master
Reset
Implicit
Master
Explicit
Master
External
A1
A2
A3
A4
C3
C1
C2
C5
C4
B2
B1
B4
D2
D4
D3
B3
D1
Master