CY7C025AV-25AC Cypress Semiconductor Corp, CY7C025AV-25AC Datasheet - Page 7

• Manufacturer Part Number: CY7C025AV-25AC
• Description: IC,SRAM,8KX16,CMOS,QFP,100PIN,PLASTIC
• Manufacturer: Cypress Semiconductor Corp

Document #: 38-06052 Rev. *H
Table 1. Non-Contending Read/Write
Table 2. Interrupt Operation Example (assumes BUSY
Table 3. Semaphore Operation Example
Set Right INT
Reset Right INT
Set Left INT
Reset Left INT
No action
Left port writes 0 to semaphore
Right port writes 0 to semaphore
Left port writes 1 to semaphore
Left port writes 0 to semaphore
Right port writes 1 to semaphore
Left port writes 1 to semaphore
Right port writes 0 to semaphore
Right port writes 1 to semaphore
Left port writes 0 to semaphore
Left port writes 1 to semaphore
Notes:
10. If BUSY
11. If BUSY
12. See Functional Description for specific addresses by device.
9.
CE
H
H
H
X
X
X
X
L
L
L
L
L
L
L
L
See Functional Description for specific highest memory locations by device.
Function
R/W
R
L
=L, then no change.
=L, then no change.
H
H
H
H
H
X
X
X
X
X
L
Function
L
L
L
Flag
R
L
Flag
R
Flag
Flag
OE
H
X
X
X
X
X
X
X
X
X
L
L
L
L
L
Inputs
R/W
X
X
X
L
UB
X
H
H
H
X
X
H
X
H
X
L
L
L
L
L
L
CE
I/O
X
X
L
L
LB
L
0
X
H
H
H
X
X
H
X
H
X
L
L
L
L
L
–I/O
1
0
0
1
1
0
1
1
1
0
1
OE
17
X
X
X
L
Left I/O
Left Port
L
SEM
H
H
H
H
H
H
H
H
X
L
L
L
L
L
L
1FFE
0
High Z
High Z
Data In
High Z
Data In
Data Out
High Z
Data Out
High Z
Data Out
Data Out
Data In
Data In
A
FFF
–I/O
0L–13L
L
X
X
1
1
1
1
0
0
1
0
1
1
1
I/O
[12]
= BUSY
17
[12]
Right
9
–I/O
17
R
Semaphore-free
Left Port has semaphore token
No change. Right side has no write access to semaphore
Right port obtains semaphore token
No change. Left port has no write access to semaphore
Left port obtains semaphore token
Semaphore-free
Right port has semaphore token
Semaphore free
Left port has semaphore token
Semaphore-free
= HIGH)
Outputs
INT
H
L
X
X
[10]
[11]
L
High Z
High Z
High Z
Data In
Data In
High Z
Data Out
Data Out
High Z
Data Out
Data Out
Data In
Data In
[9]
R/W
I/O
CY7C0241AV/0251AV/036AV
X
X
X
L
0
R
–I/O
CY7C024AV/025AV/026AV
CE
8
X
X
L
L
R
Deselected: Power-Down
Deselected: Power-Down
Write to Upper Byte Only
Write to Lower Byte Only
Write to Both Bytes
Read Upper Byte Only
Read Lower Byte Only
Read Both Bytes
Outputs Disabled
Read Data in Semaphore Flag
Read Data in Semaphore Flag
Write D
Write D
Not Allowed
Not Allowed
Status
OE
X
X
X
L
Right Port
R
IN0
IN0
1FFE (or 1/3FFE)
FFF (or 1/3FFF)
into Semaphore Flag
into Semaphore Flag
Operation
A
0R–13R
X
X
Page 7 of 19
INT
H
L
X
X
[11]
[10]
R