VG36644041DT / VG36648041DT / VG36641641DT
CMOS Synchronous Dynamic RAM
VIS
2.4 Operative Command Table (note 1)
(1/3)
HCurrent state CS RAS CAS WE
Address
Command
DESL
NOP or BST
Action
Nop or Power down
Nop or Power down
Notes
Idle
H
L
L
L
L
L
L
L
H
L
L
L
L
L
L
L
H
X
H
H
H
L
X
H
L
X
X
H
L
X
X
2
2
3
3
BA, CA, A10 READ/READA ILLEGAL
BA, CA, A10 WRIT/WRITA ILLEGAL
L
H
H
L
H
L
BR, RA
ACT
Row active
L
BA, A10
PRE/PALL
REF/SELF
MPS
Nop
L
H
L
X
Refresh or Self refresh
4
L
L
Op-Code
Mode register access
Row active
X
H
H
H
L
X
H
L
X
X
H
L
X
X
DESL
Nop
Nop
NOP or BST
BA, CA, A10 READ/READA Begin read : Determine AP
BA, CA, A10 WRIT/WRITA Begin write : Determine AP
5
5
3
6
L
H
H
L
H
L
BA, RA
BA, A10
X
ACT
ILLEGAL
Precharge
ILLEGAL
ILLEGAL
L
PRE/PALL
REF/SELF
MRS
L
H
L
L
L
Op-Code
X
Read
X
X
X
DESL
Continue burst to end ® Row active
Continue burst to end ® Row active
Burst stop ® Row active
L
H
H
H
X
X
NOP
BST
L
L
L
L
L
L
L
H
H
H
H
L
H
L
L
H
L
BA, CA, A10 READ/READA Term burst, new read : Determine AP
BA, CA, A10 WRIT/WRITA Term burst, start write : Determine AP
7
7,8
3
L
H
H
L
H
L
BA, RA
BA, A10
X
ACT
ILLEGAL
L
PRE/PALL
REF/SELF
MRS
Term burst, precharging
ILLEGAL
L
H
L
L
L
Op-Code
X
ILLEGAL
Write
X
X
X
DESL
Continue burst to end ® write recovering
Continue burst to end ® write recovering
Burst stop ® Row active
L
L
H
H
H
H
H
L
X
X
NOP
BST
L
L
L
L
L
L
H
H
L
L
L
L
L
L
H
L
BA, CA, A10 READ/READA Term burst, start read : Determine AP
BA, CA, A10 WRIT/WRITA Term burst, new write : Determine AP
7,8
7
H
H
L
H
L
BA, RA
BA, A10
X
ACT
ILLEGAL
3
PRE/PALL
REF/SELF
MRS
Term burst, precharging
ILLEGAL
9
H
L
L
Op-Code
ILLEGAL
Document :1G5-0177
Rev.2
Page11
VML [ VANGUARD INTERNATIONAL SEMICONDUCTOR ]
