
Applied Micro Circuits Corporation
6195 Lusk Blvd., San Diego, CA 92121 (619) 450-9333
6-10
PCI CONTROLLER
S5933
DEVICE SPECIFICATION
6.9
ADD-ON INTERRUPT CONTROL/
STATUS REGISTER (AINT)
Register Name:
Add-On Interrupt Control and
Status
Add-On Address Offset: 38h
Power-up value:
00000000h
Attribute:
Read/Write,
Read/Write_One_Clear
Size:
32 bits
This register provides the method for choosing which
conditions are to produce an interrupt on the Add-On
bus interface, a method for viewing the cause for the
interrupt, and a method for acknowledging (remov-
ing) the interrupt’s assertion.
Interrupt sources:
One of the Incoming mailboxes (1,2,3 or 4)
becomes full.
One of the Outgoing mailboxes (1,2,3 or 4)
becomes empty.
Built-in self test issued.
Write Transfer Count = zero
Read Transfer Count = zero
Target/Master Abort
Figure 6-4. Add-On Interrupt Control/Status Register
31
24 23
20 1918
21
17
12
8
4
0
Bit
Value
D4-D0 Incoming Mailbox
(Becomes Full)
D4=Enable Interrrupt
D3-D2=Mailbox #
0 0=Mailbox 1
0 1=Mailbox 2
1 0=Mailbox 3
1 1=Mailbox 4
D0-D1=Byte #
0 0=Byte 0
0 1=Byte 1
1 0=Byte 2
1 1=Byte 3
D12-D8 Outgoing Mailbox (R/W)
(Goes empty)
D12=Enable Interrupt
D11-D10=Mailbox
0 0=Mailbox 1
0 1=Mailbox 2
1 0=Mailbox 3
1 1=Mailbox 4
D9-D8=Byte #
0 0=Byte 0
0 1=Byte 1
1 0=Byte 2
1 1=Byte 3
16 15 14
0 0 0 0 0 0 0 0
0
Interrupt Asserted (RO)
Bus Mastering
Error Interrupt (R/WC)
BIST (R/WC)
Read Transfer
Complete (R/WC)
Write Transfer
Complete (R/WC)
Interrupt on Read
Transfer Complete
Outgoing Mailbox
Interrupt (R/WC)
Incoming Mailbox
Interrupt (R/WC)
0 0 0
Interrupt Source (R/W)
Enable & Selection
Interrupt on Write
Transfer Complete
Interrupt Status
Interrupt Selection