Memory Controller
MPC561/MPC563 Reference Manual, Rev. 1.2
Freescale Semiconductor
10-15
•
Total cycle length = 5, is determined as follows:
— Two clocks for basic cycle
— SCY = 1 determines 1 wait state, which is multiplied by two due to TRLX being set (2 + (SCY
x 2)).
— Extra clock is added due to TRLX effect on the strobes.
Figure 10-11. Relaxed Timing — Read Access (ACS = 11, SCY = 1, TRLX = 1)
through
are examples of write accesses using relaxed timing. In
,
note the following points:
•
Because TRLX is set, assertion of the CS and WE strobes is delayed by one clock cycle.
•
CS assertion is delayed an additional one quarter clock cycle because ACS = 10.
•
The total cycle length = three clock cycles, determined as follows:
— The basic memory cycle requires two clock cycles.
— An extra clock cycle is required due to the effect of TRLX on the strobes.
CLOCK
Address
TS
TA
CS
RD/WR
WE/BE
Data
OE
ACS = ‘11’ & TRLX = ‘1’
ACS = ‘00’ & TRLX = ‘1’
WEBS = ‘1’,Line Acts as BE
in Read.
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...