mcf5282 Freescale Semiconductor, Inc, mcf5282 Datasheet - Page 286

• Manufacturer Part Number: mcf5282
• Manufacturer: Freescale Semiconductor, Inc

Synchronous DRAM Controller Module
Note that in synchronous operation, burst mode and address incrementing during burst cycles are
controlled by the DRAM controller. Thus, instead of the SDRAM enabling its internal burst incrementing
capability, the processor controls this function. This means that the burst function that is enabled in the
mode register of SDRAMs must be disabled when interfacing to the processor.
Figure 15-6
delay (t
data out), this value is also 2 system clock cycles. Notice that
A
Figure 15-7
SRAS-to-SCAS delay (t
and a burst write cycle completes two cycles sooner than a burst read cycle with the same t
bus cycle is initiated sooner, but cannot begin an SDRAM cycle until the precharge-to-
completes.
15-14
PALL
SDRAM_CS[0] or [1]
RCD
command is executed one cycle after the last data transfer.
) of 2 system clock cycles. Because t
CLKOUT
DRAMW
shows a burst read operation. In this example, DACR[CASL] = 01 for an SRAS-to-SCAS
shows the burst write operation. In this example, DACR[CASL] = 01, which creates an
A[23:0]
D[31:0]
BS[3:0]
SRAS
SCAS
RCD
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3
t
RCD
ACTV
Row
) of 2 system clock cycles. Note that data is available upon SCAS assertion
= 2
Figure 15-6. Burst Read SDRAM Access
NOP
Column Column Column
READ
t
CASL
RCD
READ
= 2
is equal to the read CAS latency (SCAS assertion to
READ
NOP
Column
s are executed until the last data is read.
READ
NOP
t
EP
NOP
Freescale Semiconductor
PALL
RCD.
ACTV
The next
delay