MPC563XM Reference Manual, Rev. 1
Freescale Semiconductor
377
Preliminary—Subject to Change Without Notice
describe read and write cycles from an external master accessing internal
space in the MCU. Note that the minimal latency for an external master access is 3 clock cycles. The actual
latency of an external to internal cycle is device-specific, and varies depending on which internal block is
being accessed and how much internal bus traffic is going on at the time of the access.
Figure 13-42. External Master Read from MCU
CLKOUT
ADDR[8:31]
TS (input)
RD_WR
TSIZ[0:1]
DATA[0:31]
TA (output)
DATA is valid
Minimum 2 Wait States
BR (input)
BG
BB
receive bus grant and bus busy negated for 2nd cycle
assert BB, drive address and assert TS
Using the Internal arbiter
BDIP
*
* If the external master is another MCU with this EBI, then BB and other control pins are turned off as
shown due to use of latched TA internally. This extra cycle is not required by the slave EBI.