Altera RapidIO MegaCore Function - Manual (Page 74)

4–28 Chapter 4: Functional Description
Logical Layer Modules
RapidIO MegaCore Function August 2014 Altera Corporation
User Guide
Maintenance Register
The Maintenance Register module implements all of the control and status registers
required by this module to perform its functions. These include registers described in
Table 6–26 on page 6–16 through Table 6–32 on page 6–18 . These registers are
accessible through the System Maintenance Avalon-MM interface.
Maintenance Slave Processor
The Maintenance Slave Processor module performs the following tasks:
■ For an Avalon read, composes the RapidIO logical header fields of a MAINTENANCE
read request packet
■ For an Avalon write, composes the RapidIO logical header fields of a MAINTENANCE
write request packet
■ Maintains status related to the composed MAINTENANCE packet
■ Presents the composed MAINTENANCE packet to the Transport layer for transmission
The Avalon-MM slave interface allows you to initiate a MAINTENANCE read or write
operation. The Avalon-MM slave interface supports the following Avalon transfers:
■ Single slave write transfer with variable wait-states
■ Pipelined read transfers with variable latency
1
At any time, there can be a maximum of 64 outstanding MAINTENANCE requests that can
be MAINTENANCE reads, MAINTENANCE writes, or port-write requests.
f Refer to the Avalon Interface Specifications for more details on the supported transfers.
Figure 4–12. Maintenance Module Block Diagram
Transport Layer
maintenance
register
Register
Interface
Concentrator
System Maintenance
Avalon-MM Slave Interface
slave
processor
master
processor
port_write
processor
Avalon-MM
Slave
Avalon-MM
Slave
Avalon-MM
Master
Tx Interface Rx Interface
Maintenance
Avalon-MM Slave
Interface
Maintenance
Avalon-MM Master
Interface