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3 column address to first data out—cas latency, 4 last data out to precharge, Column address to first data outñcas latency -40 – Motorola MPC8260 User Manual

Page 316: Last data out to precharge -40, Cl = 2 (2 clock cycles) -40, Ldotopre = 2 (-2 clock cycles) -40, See section 10.4.6.4, òlast data out to precharge, 3 column address to first data outñcas latency

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10-40

MPC8260 PowerQUICC II UserÕs Manual

MOTOROLA

Part III. The Hardware Interface

10.4.6.3 Column Address to First Data OutÑCAS Latency

This parameter, controlled by P/LSDMR[CL], deÞnes the timing for Þrst read data after a
column address is sampled by the SDRAM.

Figure 10-22. CL = 2 (2 Clock Cycles)

10.4.6.4 Last Data Out to Precharge

This parameter, controlled by P/LSDMR[LDOTOPRE], deÞnes the earliest timing for the

PRECHARGE

command after the last data was read from the SDRAM. It is always related to

the CL parameter.

Figure 10-23. LDOTOPRE = 2 (-2 Clock Cycles)

CLK

ALE

CSn

SDRAS

SDCAS

MA[0Ð11]

Row

Column

WE

DQMn

Data

D0

D1

D2

D3

Activate

Read

First data out

CL = 2

CLK

ALE

CS

SDRAS

SDCAS

MA[0Ð11]

Row

Column

WE

Data

D0

D1

D2

D3

Activate

Read

Deactivate

Last Data Out

LDOTOPRE = 2

DQM