User Manual

AT75C220
56
• 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
00
Level-sensitive Low-level sensitive
01
Edge-triggered Negative-edge triggered
10
Level-sensitive High-level sensitive
11
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
76543210
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
76543210
IRQV