Intel
®
81341 and 81342 I/O Processors
December 2007
Developer’s Manual
Order Number: 315037-002US
425
Messaging Unit—Intel
®
81341 and 81342
4.9
Register Definitions
The following registers are located in the Host I/O Interface address space and in the
Peripheral Memory-Mapped Register (PMMR) address space. They are accessible
through host I/O interface bus transactions and through Intel XScale
®
processor
internal bus accesses. In the Host I/O Interface address space, they are mapped into
the first 80 bytes of the inbound address window of the ATU.
• Inbound Message 0 Register
• Inbound Message 1 Register
• Outbound Message 0 Register
• Outbound Message 1 Register
• Inbound Doorbell Register
• Inbound Interrupt Status Register
• Inbound Interrupt Mask Register
• Outbound Doorbell Register
• Outbound Interrupt Status Register
• Outbound Interrupt Mask Register
• Inbound Reset Control and Status Register
• Outbound Reset Control and Status Register
• MSI Inbound Message Register
The following registers are located in the Peripheral Memory-Mapped Register (PMMR)
address space as described in
Chapter 21.0, “Peripheral Registers”
.
• MU Configuration Register
• Queue Base Address Register
• Inbound Free Head Pointer Register
• Inbound Free Tail Pointer Register
• Inbound Post Head Pointer Register
• Inbound Post Tail Pointer Register
• Outbound Free Head Pointer Register
• Outbound Free Tail Pointer Register
• Outbound Post Head Pointer Register
• Outbound Post Tail Pointer Register
• Index Address Register
• MU Base Address Register
• MU Upper Base Address Register
Reading or writing a register that is reserved is undefined.