IDT7028 Integrated Device Technology, IDT7028 Datasheet - Page 4

• Manufacturer Part Number: IDT7028
• Description: 64k X16 Dual-port Ram
• Manufacturer: Integrated Device Technology

Truth Table I: Chip Enable
NOTES:
1. There are eight semaphore flags written to via I/O
2. Refer to Chip Enable Truth Table.
NOTES:
1. Chip Enable references are shown above with the actual CE
2. 'H' = V
3. CMOS standby requires 'X' to be either < 0.2V or > V
Truth Table II: Non-Contention Read/Write Control
NOTES:
1. A
2. Refer to Chip Enable Truth Table.
Truth Table III: Semaphore Read/Write Control
IDT7028L
High-Speed 64K x 16 Dual-Port Static RAM
CE
CE
CE
L
H
0L
H
X
X
H
X
H
X
L
L
L
L
L
L
L
L
(2)
(2)
– A
IH
15L
and 'L' = V
>V
≠ A
< 0.2V
CC
R/W
R/W
CE
V
V
0R
X
X
H
H
H
X
H
H
↑
↑
X
X
X
X
L
L
L
IL
IH
-0.2V
0
– A
IL
.
15R.
OE
OE
X
X
X
X
X
H
X
X
X
X
L
L
L
L
L
>V
Inputs
Inputs
<0.2V
CC
CE
V
V
X
X
IH
IL
-0.2V
1
(1)
(1)
UB
UB
X
H
H
H
X
X
H
X
H
X
L
L
L
L
L
Port Selected (TTL Active)
Port Selected (CMOS Active)
Port Deselected (TTL Inactive)
Port Deselected (TTL Inactive)
Port Deselected (CMOS Inactive)
Port Deselected (CMOS Inactive)
0
and read from all the I/Os (I/O
CC
(1,2)
LB
LB
X
H
H
H
X
X
H
X
H
X
L
L
L
L
L
- 0.2V.
0
and CE
SEM
SEM
H
H
H
H
H
H
H
H
X
1
L
L
L
L
L
L
levels, CE is a reference only.
4
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
0
High-Z
High-Z
High-Z
High-Z
High-Z
I/O
I/O
-I/O
______
______
8-15
8-15
15
OUT
OUT
OUT
OUT
IN
IN
IN
IN
). These eight semaphore flags are addressed by A
Outputs
Outputs
DATA
DATA
DATA
DATA
DATA
DATA
DATA
DATA
High-Z
High-Z
High-Z
High-Z
High-Z
Industrial and Commercial Temperature Ranges
I/O
I/O
______
______
Mode
0-7
0-7
(1)
OUT
OUT
OUT
OUT
IN
IN
IN
IN
Deselected: Power-Down
Both Bytes Deselected
Read Upper Byte Only
Read Lower Byte Only
Read Both Bytes
Outputs Disabled
Read Data in Semaphore Flag
Read Data in Semaphore Flag
Not Allowed
Not Allowed
Write to Upper Byte Only
Write to Lower Byte Only
Write to Both Bytes
Write I/O
Write I/O
0
0
into Semaphore Flag
into Semaphore Flag
Mode
Mode
0
-A
2
.
4836 tbl 07
4836 tbl 08
4836 tbl 06