MPC555
/
MPC556
EXTERNAL BUS INTERFACE
MOTOROLA
USER’S MANUAL
Rev. 15 October 2000
9-18
Figure 9-11 Basic Flow Diagram Of A Burst Read Cycle
Master
Slave
Request Bus (BR)
Receive bus grant (BG) from arbiter
Assert Bus Busy (BB) if No Other Master is Driving
Assert Transfer Start (TS)
Drive Address and Attributes
Receive Address
Return Data
Assert Transfer Acknowledge (TA)
Receive Data
Drive BURST Asserted
Assert BDIP
BDIP Asserted
Yes
Return Data
Assert Transfer Acknowledge (TA)
Receive Data
BDIP Asserted
Yes
Return Data
Assert Transfer Acknowledge (TA)
Receive Data
BDIP Asserted
Yes
Return Data
Assert Transfer Acknowledge (TA)
Receive Sata
BDIP Asserted
Yes
Negate Burst Data in Progress (BDIP)
No
Drive Last Data
& Assert TA
No
Drive Last Data
& Assert TA
No
Drive Last Data
& Assert TA
No
Drive Last Data
& Assert TA
ADDR[28:29] mod 4 = ?
Assert BDIP
Assert BDIP
= 2
= 1
= 3
= 0
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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