HYB39S13620TQ- Datasheet, PDF (16/70 Pages) Siemens Semiconductor Group – Special Mode Registers Two color registers Burst Read with Single Write Operation

HYB 39S16320TQ-6/-7/-8
Active (ACT)
The ACT command is used to open (or activate) a row in a particular bank. The value on BA selects
the bank and the address provided on input pins A9 - A0 selects the row. This row remains open
for accesses until a Precharge command is issued to the bank. A Precharge command must be
issued before opening a different row in the same bank.
Active with WPB (ACTM)
ACTM command is similar to the ACT command, except that the Write-per-Bit mask is activated.
Any Write or Block Write cycles to the selected bank/row while active will be masked according to
the contents of the Mask Register.
Read (RD)
The Read command is used to initiate a burst read access from an active row. The value on BA
selects the bank and the address provided on inputs A7 - A0 selects the starting column location.
The value on A8 determines whether or not Auto Precharge is used. If A8 is “1”, Auto Precharge is
used. If Auto Precharge is selected, the row being accessed will be precharged at the end of the
read burst; if Auto Precharge is not selected, the row will remain open for subsequent accesses. If
a particular DQM was registered high, the corresponding DQs appearing 2 clocks later on the
output pins will be High-Z.
Write (WR)
The Write command is used to initiate a burst write access to an active row. The value on BA selects
the bank and the address provided on inputs A7 -A0 selects the starting column location. The value
on A8 determines whether or not Auto Precharge is used. If A8 is “1”, Auto Precharge is used. If
Auto Precharge is selected, the row being accessed will be precharged at the end of write burst; if
Auto Precharge is not selected, the row will remain open for subsequent accesses. If a particular
DQM is registered high, the corresponding data inputs will be ignored and the write will not be
executed to that byte location.
Block Write (BW)
The Block Write command is used to write a single data value to the block of eight consecutive
column locations addressed by inputs A7 - A3 . The data is provided by the Color Register which
must be loaded prior to the Block Write cycle by invoking LSMR cycle. If the two Color Register
option is enabled, the address line A0 is used to select the desired Color Register. A “0” at A0
selects Color Register 0, a “1” Color Register 1. The input data on DQs which is registered
coincident with the Block Write command is used to mask specific column/byte combinations within
the block. The DQM signals operate the same way as for Write cycles, but are applied to all eight
columns in the selected block.
Semiconductor Group
16
1998-10-01