IS42S16100E, IC42S16100E
Write Cycle (Full Page) Interruption Using
the Burst Stop Command
must be executed within the ACT to PRE command
period (tr a s max.) following the burst stop command.
After the period (tw b d ) required for burst data input to
stop following the execution of the burst stop command
has elapsed, the write cycle terminates. This period
(tw b d ) is zero clock cycles, regardless of the CAS
latency.
The IS42S16100E/IC42S16100E can input data
continuously from the burst start address (a) to location
a+255 during a write cycle in which the burst length
is set to full page. The IS42S16100E/IC42S16100E
repeats the operation starting at the 256th cycle with
data input returning to location (a) and continuing with
a+1, a+2, a+3, etc. A burst stop command must be
executed to terminate this cycle. A precharge command
CLK
t
WBD=0
BST
INVALID DATA
tRP
PRE 0
COMMAND
DQ
WRITE A0
DIN A0
DIN A1
DIN
A
DIN A1
DIN A2
READ (CA=A, BANK 0)
BURST STOP PRECHARGE (BANK 0)
Don't Care
Burst Data Interruption Using the U/LDQM
Pins (Read Cycle)
output control operates independently on a byte basis
with the UDQM pin controlling upper byte output (pins
DQ8-DQ15) and the LDQM pin controlling lower byte
output (pins DQ0 to DQ7).
Burst data output can be temporarily interrupted (masked)
during a read cycle using the U/LDQM pins. Regardless of
the CAS latency, two clock cycles (tq m d ) after one of the
U/LDQM pins goes HIGH, the corresponding outputs go
to the HIGH impedance state. Subsequently, the outputs
are maintained in the high impedance state as long as
that U/LDQM pin remains HIGH. When the U/LDQM pin
goes LOW, output is resumed at a time tq m d later. This
Since the U/LDQM pins control the device output buffers
only, the read cycle continues internally and, in particular,
incrementing of the internal burst counter continues.
CLK
COMMAND
UDQM
READ A0
t
QMD=2
LDQM
DQ8-DQ15
DQ0-DQ 7
D
OUT A0
D
OUT A2
DOUT A3
HI-Z
HI-Z
DOUT A0
D
OUT A1
HI-Z
READ (CA=A, BANK 0)
DATA MASK (LOWER BYTE)
DATA MASK (UPPER BYTE)
CAS latency = 2, burstlength = 4
34
Integrated Silicon Solution, Inc. — www.issi.com
Rev. C
01/22/08
ISSI [ INTEGRATED SILICON SOLUTION, INC ]
