Motorola MPC533 Reference Manual page 351

CLKOUT
BR0
BG0
BR1
BG1
BB
ADDR[8:31]
and Attributes
TS
TA
9.5.7.4 nternal Bus Arbiter
The MPC533 can be configured at system reset to use the internal bus arbiter. In this case,
the MPC533 will be parked on the bus. The parking feature allows the MPC533 to skip the
bus request phase, and if BB is negated, assert BB and initiate the transaction without
waiting for BG from the arbiter.
The priority of the external device relative to the internal MPC533 bus masters is
programmed in the SIU module configuration register. If the external device requests the
bus and the MPC533 does not require it, or if the external device has higher priority than
the current internal bus master, the MPC533 grants the bus to the external device.
Table 9-4 describes the priority mechanism used by the internal arbiter.
MOTOROLA
PRELIMINARY—SUBJECT TO CHANGE WITHOUT NOTICE
Master 0
"Turns On" and
Drives Signals
Figure 9-26. Bus Arbitration Timing Diagram
Chapter 9. External Bus Interface
Master 0
Negates BB
"Turns On" and
and "Turns Off"
Drives Signals
(Three-state Controls)
Bus Operations
Master 1
9-35