Aic source vector registers, Aic interrupt vector registers – Rainbow Electronics AT75C220 User Manual
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AT75C220
56
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SRCTYPE: Interrupt Source Type
Programs the input to be positive- or negative-edge triggered or positive- or negative-level sensitive.
The active level or edge is not programmable for the internal sources.
AIC Source Vector Registers
Register Name: AIC_SVR0...AIC_SVR31
Access Type:Read/write
Reset Value: 0
•
Vector
In these registers, the user may store the addresses of the corresponding handler for each interrupt source.
AIC Interrupt Vector Registers
Register Name: AIC_IVR
Access Type:Read-only
Reset Value: 0
•
IRQV
The IRQ Vector Register contains the vector programmed by the user in the Source Vector Register corresponding to
the current interrupt. The SVR Register (1 to 31) is indexed by the current interrupt number when the IVR register is
read. When there is no interrupt, the IRQ register reads 0.
SRCTYPE
Internal Sources
External Sources
0
0
Level-sensitive
Low-level sensitive
0
1
Edge-triggered
Negative-edge triggered
1
0
Level-sensitive
High-level sensitive
1
1
Edge-triggered
Positive-edge triggered
31
30
29
28
27
26
25
24
Vector
23
22
21
20
19
18
17
16
Vector
15
14
13
12
11
10
9
8
Vector
7
6
5
4
3
2
1
0
Vector
31
30
29
28
27
26
25
24
IRQV
23
22
21
20
19
18
17
16
IRQV
15
14
13
12
11
10
9
8
IRQV
7
6
5
4
3
2
1
0
IRQV