Table 3.
Interrupt Flag
(1) (4)
Left Port
R/W
L
L
X
X
X
Notes:
1.
2.
3.
4.
CS
L
L
X
X
L
OE
L
X
X
X
L
A
OL
-A
12L
1FFF
X
X
1FFE
INT
L
X
X
L
(3)
H
(2)
R/W
R
X
X
L
X
CS
R
X
L
L
X
Right Port
OE
R
X
L
X
X
A
OR
-A
12R
X
1FFF
1FFE
X
INT
R
L
(2)
H
(3)
X
X
Function
Set Right INT
R
Flag
Reset Right INT
R
Flag
Set Left INT
L
Flag
Reset Left INT
L
Flag
Assumes BUSY
L
= BUSY
R
= H.
If BUSY
L
= L, then NC.
If BUSY
R
= L, then NC.
H = HIGH, L = LOW, X = DON’T CARE, NC = NO CHANGE.
Table 4.
Arbitration
(2)
Left Port
CS
L
H
L
H
L
A
0L
– A
12L
X
Any
X
≠
A
0R
– A
12R
CS
R
H
H
L
L
Right Port
A
0R
– A
12R
X
X
Any
≠
A
0L
– A
12L
BUSY
L
H
H
H
H
Flags
(1)
BUSY
R
H
H
H
H
Function
No Contention
No Contention
No Contention
No Contention
Address Arbitration With CS Low Before Address Match
L
L
L
L
LV5R
RV5L
Same
Same
L
L
L
L
LV5R
RV5L
Same
Same
H
L
H
L
L
H
L
H
L-Port Wins
R-Port Wins
Arbitration Resolved
Arbitration Resolved
CS Arbitration With Address Match Before CS
LL5R
RL5L
LW5R
LW5R
Notes:
= A
0R
– A
12R
= A
0R
– A
12R
= A
0R – A12R
= A
0R
– A
12R
LL5R
RL5L
LW5R
LW5R
= A
0L
– A
12L
= A
0L – A12L
= A
0L
– A
12L
= A
0L
– A
12L
H
L
H
L
L
H
L
H
L-Port Wins
R-Port Wins
Arbitration Resolved
Arbitration Resolved
1. INT Flags Don’t Care.
2. X = DON’T CARE, L = LOW, H = HIGH.
LV5R = Left Address Valid
≥
5 ns before right address.
RV5L = Right Address Valid
≥
5 ns before left address
Same = Left and Right Addresses match within 5 ns of each other.
LL5R = Left CS = LOW
≥
5 ns before Right CS.
RL5L = Right CS = LOW
≥
5 ns before left CS.
LW5R = Left and Right CS = LOW within 5 ns of each other.
9
M67025E
4146J–AERO–06/03
ATMEL [ ATMEL CORPORATION ]
