CY7C024/0241
CY7C025/0251
Table 2. Interrupt Operation Example (Assumes BUSY
L
=BUSY
R
=HIGH)
Left Port
Function
Set Right INT
R
Flag
Reset Right INT
R
Flag
Set Left INT
L
Flag
Reset Left INT
L
Flag
Table 3. Semaphore Operation Example
Function
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
I/O
0
–I/O
15/17
Left
1
0
0
1
1
0
1
1
1
0
1
I/O
0
–I/O
15/17
Right
1
1
1
0
0
1
1
0
1
1
1
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
Status
R/W
L
L
X
X
X
CE
L
L
X
X
L
OE
L
X
X
X
L
A
0L–11L
(1)FFF
X
X
(1)FFE
INT
L
X
X
L
H
R/W
R
X
X
L
X
CE
R
X
L
L
X
Right Port
OE
R
X
L
X
X
A
0R–11R
X
(1)FFF
(1)FFE
X
INT
R
L
H
X
X
Notes:
6. A
0L–12L
and A
0R–12R
, 1FFF/1FFE for the CY7C025.
7. If BUSY
R
=L, then no change.
8. If BUSY
L
=L, then no change.
Document #: 38-06035 Rev. *C
Page 6 of 21
CYPRESS [ CYPRESS SEMICONDUCTOR ]
