Altera CPRI v6.0 MegaCore Function User Manual
Page 104
Bits
Field Name
Type
Value on
Reset
Description
10:8
loop_
reversed
RW
3'b0
Testing reverse loopback mode. If you turn on Enable reverse
loopback path (Rx to Tx) in the CPRI v6.0 parameter editor,
this register field specifies the parts of the CPRI frame that are
sent on the reverse loopback path. If you do not turn on this
parameter, you should leave this register field at its default
value of 3'b0.
For standard testing, you would turn on these loopback modes
in a CPRI RE slave only.
This field has the following valid values:
• 3'b000: No loopback.
• 3'b001: Full CPRI frame loopback. Incoming CPR data and
control words are sent back as-is in outgoing CPR
communication.
• 3'b010: I/Q data loopback. Incoming CPRI data are sent
back in outgoing CPRI communication; control words are
generated locally.
• 3'b011: Fast control and management loopback. Incoming
CPRI fast control and management (Ethernet) control and
data words are sent back in outgoing CPRI communication;
remaining data and control words are generated locally.
• 3'b100: Fast control and management and VS loopback.
Incoming CPRI fast control and management (Ethernet)
and vendor-specific control words are sent back in outgoing
CPRI communication; data and remaining control words
are generated locally.
7:2
Reserved
UR0
6'b0
UG-01156
2015.02.16
LOOPBACK Register
5-15
CPRI v6.0 IP Core Registers
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