S5920Q Applied Micro Circuits Corporation, S5920Q Datasheet - Page 116

• Manufacturer Part Number: S5920Q
• Manufacturer: Applied Micro Circuits Corporation

Specifications of S5920Q

• Operating Temperature (min): 0C
• Operating Temperature Classification: Commercial
• Operating Temperature (max): 70C
• Package Type: PQFP
• Rad Hardened: No
• Lead Free Status / Rohs Status: Not Compliant

S5920 – PCI Product: Mailbox Overview
Servicing a PCI Mailbox Interrupt (INTA# asserted):
Servicing the Add-On mailbox interrupt (IRQ# asserted):
AMCC Confidential and Proprietary
1. Identify the interrupt source(s). Multiple interrupt sources are available on the S5920. The interrupt service
2. Check mailbox status. The mailbox status bits indicate which mailbox bytes must be read or written.
3. Access the mailbox. Based on the contents of MBEF, mailboxes are read or written. Reading an incoming
4. Clear the interrupt source. The PCI INTA# signal is deasserted by clearing the interrupt request. The request
1. Identify the interrupt source(s). Multiple interrupt sources are available on the S5920. The interrupt service
2. Check mailbox status. The mailbox status bits indicate which mailbox bytes must be read or written.
3. Access the mailbox. Based on the contents of AMBEF, mailboxes are read or written. Reading the incoming
routine must verify that a mailbox generated the interrupt (and not some other interrupt source).
mailbox byte clears the corresponding status bit in MBEF.
is cleared by writing a 1 to the appropriate bit.
routine must verify that a mailbox generated the interrupt (and not some other interrupt source).
mailbox byte clears the corresponding status bit in AMBEF.
INTCSR
INTCSR
INTCSR
MBEF
MBEF
OMB
IMB
INTCSR
INTCSR
AINT
AINT
AINT
AMBEF
AMBEF
AIMB
AOMB
Bit 23
Bit 17
Bit 16
Bits 31:28
Bits 15:12
Bits 31:0
Bits 31:0
Bit 17
Bit 16
Bit 23
Bit 17
Bit 16
Bits 31:28
Bits 15:12
Bits 31:0
Bits 31:0
PCI interrupt asserted
PCI incoming mailbox interrupt indicator
PCI outgoing mailbox interrupt indicator
Full PCI incoming mailbox bytes
Empty PCI outgoing mailbox bytes
PCI outgoing mailboxes
PCI incoming mailboxes
Clear PCI incoming mailbox interrupt
Clear PCI outgoing mailbox interrupt
Add-On interrupt asserted
Add-On outgoing mailbox interrupt indicator
Add-On incoming mailbox interrupt indicator
Empty Add-On outgoing mailbox bytes
Full Add-On incoming mailbox bytes
Add-On incoming mailbox
Add-On outgoing mailbox
Revision 1.02 – April 12, 2007
Data Book
DS1596
116