Specifications

Interrupt Controller (V40)
IPFW
IPFW selects fixed or rotating priorities and the method of
informing the ICU that an interrupt has been serviced. Operation
of the ICU can be changed at any time by writing a new IPFW.
Refer to Figure 8-8 when programming the IPFW.
IPFW
Address: Base + 0
Access: Write
76543210
IL2 IL1 IL0
Requesting Input
000 INT0
001 INT1
010 INT2
011 INT3
100 INT4
101 INT5
110 INT6
111 INT7
00RP SIL FI
End of Interrupt
001 Non-specific FI
011 Specific FI
Automatic Rotation
101 Rotate on non-specific FI
100 Rotate in auto FI (SET)
000 Rotate in auto FI (CLR)
Specific Rotation
111 Rotate on specific FI
110 Set priority command
010 No operation (do not use)
Figure 8–8. Interrupt Priority and Finish Word.
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