k4h560838c Samsung Semiconductor, Inc., k4h560838c Datasheet - Page 33

• Manufacturer Part Number: k4h560838c
• Description: Ddr Sdram Specification Version 0.6
• Manufacturer: Samsung Semiconductor, Inc.

256Mb C-die(x4/8) DDR SDRAM
4. Command Truth Table
1. OP Code : Operand Code. A
2.EMRS/ MRS can be issued only at all banks precharge state.
3. Auto refresh functions are same as the CBR refresh of DRAM.
4. BA
5. If A
6. During burst write with auto precharge, new read/write command can not be issued.
7. Burst stop command is valid at every burst length.
8. DM sampled at the rising and falling edges of the DQS and Data-in are masked at the both edges (Write DM latency is 0).
9. This combination is not defined for any function, which means "No Operation(NOP)" in DDR SDRAM.
Register
Register
Refresh
Bank Active & Row Addr.
Read &
Column Address
Write &
Column Address
Burst Stop
Precharge
Active Power Down
Precharge Power Down Mode
DM
No operation (NOP) : Not defined
A new command can be issued 2 clock cycles after EMRS or MRS.
The automatical precharge without row precharge command is meant by "Auto".
Auto/self refresh can be issued only at all banks precharge state.
If both BA
If both BA
If both BA
If both BA
Another bank read/write command can be issued after the end of burst.
New row active of the associated bank can be issued at t
0
10
~ BA
/AP is "High" at row precharge, BA
1
0
0
0
0
: Bank select addresses.
and BA
is "High" and BA
is "Low" and BA
and BA
COMMAND
Extended MRS
Mode Register Set
Auto Refresh
Self
Refresh
Auto Precharge Disable
Auto Precharge Enable
Auto Precharge Disable
Auto Precharge Enable
Bank Selection
All Banks
1
1
are "Low" at read, write, row active and precharge, bank A is selected.
are "High" at read, write, row active and precharge, bank D is selected.
1
1
is "High" at read, write, row active and precharge, bank C is selected.
is "Low" at read, write, row active and precharge, bank B is selected.
0
~ A
Table 8. Command truth table
Entry
Entry
Entry
Exit
Exit
Exit
11
& BA
0
and BA
0
~ BA
CKEn-1
H
H
H
L
H
H
H
H
H
H
L
H
L
H
H
1
1
are ignored and all banks are selected.
: Program keys. (@EMRS/MRS)
CKEn
RP
- 33 -
H
H
H
H
(V=Valid, X=Don t Care, H=Logic High, L=Logic Low)
X
X
L
X
X
X
X
X
L
L
X
after the end of burst.
CS
H
H
X
H
H
H
L
L
L
L
L
L
L
L
L
L
L
L
L
RAS
X
H
X
H
H
H
X
V
X
X
H
X
V
X
H
L
L
L
L
L
CAS
H
H
H
H
H
H
L
L
L
X
L
L
X
V
X
X
X
V
X
WE
L
L
H
H
X
H
H
L
L
L
X
V
X
X
H
X
V
X
H
REV. 0.7 Jan. 31. 2002
BA
V
V
V
V
X
0,1
A
OP CODE
OP CODE
10
H
H
H
Row Address
L
L
L
/AP
X
X
X
X
X
X
X
A
Address
Address
A
Column
Column
9
11,
~ A
X
A
12
0
Note
1, 2
1, 2
4, 6
3
3
3
3
4
4
4
7
5
8
9
9