Discontinued (8/99 - last order; 12/99 - last ship)
IBM0364804 IBM0364164
IBM0364404 IBM03644B4
64Mb Synchronous DRAM - Die Revision B
Burst Stop Command
Once a burst read or write operation has been initiated, there exist several methods in which to terminate the
burst operation prematurely. These methods include using another Read or Write Command to interrupt an
existing burst operation or using a Precharge Command to interrupt a burst cycle and close the active bank.
When interrupting a burst with another Read or Write Command care must be taken to avoid DQ contention.
If the burst length is full page, the Burst Stop Command may also be used to terminate the existing burst
operation but leave the bank open for future Read or Write Commands to the same page of the active bank.
Use of the Burst Stop Command during other burst length operations is illegal. The Burst Stop Command is
defined by having RAS and CAS high with CS and WE low at the rising edge of the clock.
When using the Burst Stop Command during a burst read cycle, the data DQs go to a high impedance state
after a delay which is equal to the CAS Latency set in the Mode Register.
Termination of a Burst Read Operation
(Burst Length = Full Page, CAS Latency = 2, 3)
T0
T1
T2
T3
T4
T5
T6
T7
T8
CLK
Burst
Stop
READ A
NOP
NOP
NOP
NOP
NOP
NOP
NOP
COMMAND
The burst ends after a delay equal to the CAS latency.
DOUT A3
CAS latency = 2
DOUT A0
DOUT A1
DOUT A0
DOUT A2
DOUT A1
tCK2, DQs
CAS latency = 3
DOUT A2
DOUT A3
tCK3, DQs
If a Burst Stop Command is issued during a full page burst write operation, then any residual data from the
burst write cycle will be ignored. Data that is presented on the DQ pins before the Burst Stop Command is
registered will be written to the memory.
Termination of a Burst Write Operation
(Burst Length = Full Page, CAS Latency = 2, 3)
T0
T1
T2
T3
T4
T5
T6
T7
T8
CLK
Burst
NOP
WRITE A
DIN A0
NOP
NOP
NOP
NOP
NOP
NOP
COMMAND
Stop
CAS latency = 2,3
don’t care
DIN A1
DIN A2
DQs
Input data for the Write is masked.
©IBM Corporation. All rights reserved.
Use is further subject to the provisions at the end of this document.
19L3264.E35855A
1/28/99
Page 19 of 72
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