External Bus Interface
MPC561/MPC563 Reference Manual, Rev. 1.2
9-34
Freescale Semiconductor
9.5.7.3
Bus Busy
BB assertion indicates that the current bus master is using the bus. New masters should not begin transfer
until this signal is negated. The bus owner should not relinquish or negate this signal until the transfer is
complete. To avoid contention on the BB line, the master should three-state this signal when it gets a
logical one value. This requires the connection of an external pull-up resistor to ensure that a master that
acquires the bus is able to recognize the BB line negated, regardless of how many cycles have passed since
the previous master relinquished the bus. Refer to
Figure 9-25. Master Signals Basic Connection
External Bus
Slave 2
Master
TS
BB
MPC500 Device
(Slave 1)
Summary of Contents for MPC561
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Page 144: ...Signal Descriptions MPC561 MPC563 Reference Manual Rev 1 2 2 46 Freescale Semiconductor...
Page 206: ...Central Processing Unit MPC561 MPC563 Reference Manual Rev 1 2 3 62 Freescale Semiconductor...
Page 302: ...Reset MPC561 MPC563 Reference Manual Rev 1 2 7 14 Freescale Semiconductor...
Page 854: ...Time Processor Unit 3 MPC561 MPC563 Reference Manual Rev 1 2 19 24 Freescale Semiconductor...
Page 968: ...Development Support MPC561 MPC563 Reference Manual Rev 1 2 23 54 Freescale Semiconductor...
Page 1144: ...Internal Memory Map MPC561 MPC563 Reference Manual Rev 1 2 B 34 Freescale Semiconductor...
Page 1212: ...TPU3 ROM Functions MPC561 MPC563 Reference Manual Rev 1 2 D 60 Freescale Semiconductor...
Page 1216: ...Memory Access Timing MPC561 MPC563 Reference Manual Rev 1 2 E 4 Freescale Semiconductor...