NXP Semiconductors MPC5566, Reference Manual

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External Bus Interface (EBI)
MPC5566 Microcontroller Reference Manual, Rev. 2
Freescale Semiconductor 12-45
12.4.2.6.1 Small Access Example #1: 32-bit Write to 16-bit Port
Figure 12-27 shows an example of a 32-bit write to a 16-bit port, requiring two 16-bit external transactions.
Figure 12-27. Single Beat 32-bit Write Cycle, 16-bit Port Size, Basic Timing
12.4.2.6.2 Small Access Example #2: 32-byte Write with External TA
Figure 12-28 shows an example of a 32-byte write to a non-chip select device, such as an external master,
using external TA, requiring eight 32-bit external transactions. Due to the use of external TA, RD_WR
does not toggle between the accesses unless that access is the end of a 64-bit boundary. In this case, an
extra cycle is required between TA and the next TS to get the next 64-bits of write data internally and
RD_WR negates during this extra cycle.
DATA is valid DATA is valid
CLKOUT
ADDR[8:31]
TS
DATA[0:31]
TA
RD_ WR
TSIZ[0:1]
BDIP
WE
CS[ n ]
10
A A + 2
ABCDXXXX EFGHXXXX