V58C2128(804/404/164)S
TRUTH TABLE 3 – Current State Bank n - Command to Bank n
(Notes: 1-6; notes appear below and on next page)
CURRENT STATE
/CS
H
L
/RAS /CAS /WE
COMMAND/ACTION
NOTES
X
H
L
X
H
H
L
X
H
H
H
L
DESELECT (NOP/continue previous operation)
NO OPERATION (NOP/continue previous operation)
ACTIVE (select and activate row)
Any
L
Idle
L
L
AUTO REFRESH
7
7
L
L
L
MODE REGISTER SET
L
H
H
L
L
H
L
READ (select column and start READ burst)
WRITE (select column and start WRITE burst)
PRECHARGE (deactivate row in bank or banks)
READ (select column and start new READ burst)
PRECHARGE (truncate READ burst, start PRECHARGE)
BURST TERMINATE
10
10
8
Row Active
L
L
L
H
L
L
L
H
L
H
L
10
8
Read (Auto Precharge
Disabled)
L
H
H
L
L
H
H
H
L
L
9
L
H
L
READ (select column and start READ burst)
WRITE (select column and start new WRITE burst)
10, 11
10
Write (Auto Precharge
Disabled)
L
L
L
H
L
PRECHARGE (truncate WRITE burst, start PRECHARGE) 8, 11
NOTE:
t
1. This table applies when CKE was HIGH and CKE is HIGH (see Truth Table 2) and after XSR
n-1
n
has been met (if the previous state was self refresh).
2. This table is bank-specific, except where noted, i.e., the current state is for a specific bank and the commands shown
are those allowed to be issued to that bank when in that state. Exceptions are covered in the notes below.
3. Current state definitions:
t
Idle: The bank has been precharged, and RP has been met.
t
Row Active: A row in the bank has been activated, and RCD has been met.
No data bursts/accesses and no register accesses are in progress.
Read: A READ burst has been initiated, with AUTO PRECHARGE disabled,
and has not yet terminated or been terminated.
Write: A WRITE burst has been initiated, with AUTO PRECHARGE disabled,
and has not yet terminated or been terminated.
4. The following states must not be interrupted by a command issued to the same bank. DESELECT or NOP com-
mands,
or allowable commands to the other bank should be issued on any clock edge occurring during these states.
Allowable commands to the other bank are determined by its current state and Truth Table 3, and according to
Truth Table 4.
t
Precharging: Starts with registration of a PRECHARGE command and ends when RP is
t
met. Once RP is met, the bank will be in the idle state.
V58C2128(804/404/164)S Rev. 1.6 March 2002
28
MOSEL [ MOSEL VITELIC, CORP ]
