Datasheet

DRAM Controller
MOTOROLA MCF5206e USER’S MANUAL 11-37
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Clock H3
The internal transfer acknowledge asserts to indicate that the first byte read transfer of the
word burst will be completed and the data on D[31:24] will be registered on the next rising
edge of CLK.
Clock L3
With EDO DRAM, data is driven continuously on a read after the falling edge of CAS until
the next falling edge of CAS or until the rising edge of RAS. This allows the MCF5206e to
negate CAS[0] on L3 to allow more CAS precharge time. The negation of CAS[0] begins
the CAS precharge.
Clock H4
The MCF5206e negates the internal transfer acknowledge, ending the first byte read
transfer of the word burst. At this point, the new page has been opened; therefore, the
MCF5206e continues to assert RAS. The MCF5206e drives the next column address on
A[27:9].
Clock L4
The MCF5206e asserts CAS[0] to indicate the column address is valid on A[27:9]. At this
point, the EDO DRAM begins driving the data on D[31:24].
Clock H5
The internal transfer acknowledge asserts to indicate that the first byte read transfer of the
word burst will be completed and the data on D[31:24] will be registered on the next rising
edge of CLK.
Clock L5
With EDO DRAM, data is driven continuously on a read after the falling edge of CAS until
the next falling edge of CAS
or until the rising edge of RAS. This allows the MCF5206e to
negate CAS
[0] on L3 to allow more CAS precharge time. The negation of CAS[0] begins
the CAS precharge.
Clock H6
The MCF5206e negates the internal transfer acknowledge, ending the final byte read
transfer of the word burst. Because the bank is in fast page mode, MCF5206e continues
to assert RAS
. Because RAS remains asserted, the EDO DRAM continues to drive the
data from the previous read transfer on D[31:24].
Clock H7/L7
A byte read transfer to the same DRAM bank is generated internally by the ColdFire core.
This transfer misses the open page.
Fr
eescale S
emiconduct
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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