MPC564EVB Freescale Semiconductor, MPC564EVB Datasheet - Page 377

• Manufacturer Part Number: MPC564EVB
• Description: KIT EVAL FOR MPC561/562/563/564
• Manufacturer: Freescale Semiconductor
• Type: Microcontrollerr

Specifications of MPC564EVB

• Contents: Module Board, Installation Guide, Power Supply, Cable, Software and more
• Processor To Be Evaluated: MPC56x
• Data Bus Width: 32 bit
• Interface Type: RS-232, Ethernet
• For Use With/related Products: MPC561, 562, 563, 564
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

9.5.8
Address transfer phase signals include the following:
Transfer attributes signals include RD/WR, BURST, TSIZ[0:1], AT[0:3], STS, and BDIP. With the
exception of the BDIP, these signals are available at the same time as the address bus.
9.5.8.1
This signal (TS) indicates the beginning of a transaction on the bus addressing a slave device. This signal
should be asserted by a master only after the ownership of the bus was granted by the arbitration protocol.
This signal is asserted for the first cycle of the transaction only and is negated in successive clock cycles
until the end of the transaction. The master should three-state this signal when it relinquishes the bus to
avoid contention between two or more masters in this line. This situation indicates that an external pull-up
resistor should be connected to the TS signal to avoid having a slave recognize this signal as asserted when
no master drives it. Refer to
9.5.8.2
The address bus consists of 32 bits, with ADDR0 the most significant bit and ADDR31 the least significant
bit. Only 24 bits (ADDR[8:31]) are available external to the MPC561/MPC563. The bus is
byte-addressable, so each address can address one or more bytes. The address and its attributes are driven
on the bus with the transfer start signal and kept valid until the bus master receives the transfer
acknowledge signal from the slave. To distinguish the individual byte, the slave device must observe the
TSIZ signals.
9.5.8.3
A high value on the RD/WR line indicates a read access. A low value indicates a write access.
9.5.8.4
BURST is driven by the bus master at the beginning of the bus cycle along with the address to indicate that
the transfer is a burst transfer.
The MPC561/MPC563 supports a non-wrapping, 8-beat maximum (with 32-bit port), critical word first
burst type. The maximum burst size is 32 bytes. For a 16-bit port, the burst includes 16 beats. For an 8-bit
port, the burst includes 32 beats at most.
The actual size of the burst is determined by the address of the starting word of the burst. Refer to
and
Freescale Semiconductor
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•
•
Table
Transfer start
Address bus
Transfer attributes
9-6.
Address Transfer Phase Signals
Transfer Start
Address Bus
Read/Write
Burst Indicator
8- and 16-bit ports must be controlled by the memory controller.
Figure
MPC561/MPC563 Reference Manual, Rev. 1.2
9-25.
NOTE
External Bus Interface
Table 9-5
9-37