MPC564EVB Freescale Semiconductor, MPC564EVB Datasheet - Page 354

• 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

External Bus Interface
9.5.2.3
The general case of single beat transfers assumes that the external memory has a 32-bit port size. The
MPC561/MPC563 provides an effective mechanism for interfacing with 16-bit and 8-bit port size
memories, allowing transfers to these devices when they are controlled by the internal memory controller.
In this case, the MPC561/MPC563 attempts to initiate a transfer as in the normal case. If the bus interface
receives a small port size (16 or 8 bits) indication before the transfer acknowledge to the first beat (through
the internal memory controller), the MCU initiates successive transactions until the completion of the data
transfer. Note that all the transactions initiated to complete the data transfer are considered to be part of an
atomic transaction, so the MCU does not allow other unrelated master accesses or bus arbitration to
intervene between the transfers. If any of the transactions except the first is re-tried during an access to a
small port, then a machine-check exception is generated to the RCPU.
9-14
CLKOUT
BR
BG
BB
ADDR[8:31]
RD/WR
TSIZ[0:1]
BURST, BDIP
TS
Data
TA
Single Beat Flow with Small Port Size
Figure 9-9. Single Beat Basic Write Cycle Timing – One Wait State
O
O
MPC561/MPC563 Reference Manual, Rev. 1.2
Receive bus grant and bus busy negated
O
O
Assert BB, drive address and assert TS
Wait state
O
Data is sampled
Freescale Semiconductor