Memory Controller
MPC561/MPC563 Reference Manual, Rev. 1.2
10-18
Freescale Semiconductor
Figure 10-14. Relaxed Timing — Write Access (ACS = 00, SCY = 0, CSNT = 1, TRLX = 1
10.3.4
Extended Hold Time on Read Accesses
For devices that require a long disconnection time from the data bus on read accesses, the bit EHTR in the
corresponding OR register can be set. In this case any MPC561/MPC563 access to the external bus
following a read access to the referred memory bank is delayed by one clock cycle unless it is a read access
to the same bank.
through
show the effect of the EHTR bit on memory
controller timing.
shows a write access following a read access. Because EHTR = 0, no extra clock cycle is
inserted between memory cycles.
Clock
Address
TS
TA
CS
RD/
WR
WE
/
BE
Data
OE
CSNT = 1
No Effect, ACS = 00
Summary of Contents for MPC561
Page 84: ...MPC561 MPC563 Reference Manual Rev 1 2 lxxxiv Freescale Semiconductor...
Page 144: ...Signal Descriptions MPC561 MPC563 Reference Manual Rev 1 2 2 46 Freescale Semiconductor...
Page 206: ...Central Processing Unit MPC561 MPC563 Reference Manual Rev 1 2 3 62 Freescale Semiconductor...
Page 302: ...Reset MPC561 MPC563 Reference Manual Rev 1 2 7 14 Freescale Semiconductor...
Page 854: ...Time Processor Unit 3 MPC561 MPC563 Reference Manual Rev 1 2 19 24 Freescale Semiconductor...
Page 968: ...Development Support MPC561 MPC563 Reference Manual Rev 1 2 23 54 Freescale Semiconductor...
Page 1144: ...Internal Memory Map MPC561 MPC563 Reference Manual Rev 1 2 B 34 Freescale Semiconductor...
Page 1212: ...TPU3 ROM Functions MPC561 MPC563 Reference Manual Rev 1 2 D 60 Freescale Semiconductor...
Page 1216: ...Memory Access Timing MPC561 MPC563 Reference Manual Rev 1 2 E 4 Freescale Semiconductor...