4–4
Altera Corporation
Stratix II GX Device Handbook, Volume 2
October 2007
Basic Mode
Table 4–1
describes the available options on page 3 of the MegaWizard
Plug-In Manager for your ALT2GXB custom megafunction variation.
Table 4–1. MegaWizard Plug-In Manager Options (Page 3 for Basic Mode) (Part 1 of 3)
ALT2GXB Setting
Description
Reference
Which protocol will you be
using?
Determines the specific protocol or modes under
which the transceiver operates. For the Basic mode,
you must select the
Basic
protocol.
Which subprotocol will you
be using?
In Basic mode, the subprotocols are the diagnostic
modes. The available options are as follows:
●
No loopback – This is the normal operation of the
transceiver.
●
Serial loopback
–
This mode loops the user data
from the transmitter path back to the receiver path
right before the buffers. The serial loopback can
be controlled dynamically.
●
Parallel loopback/BIST – This mode loops the
parallel data from the BIST (non PRBS) back to
the BIST verifier in the receiver path. Parallel
Loopback is allowed only in Basic Double-Width
mode.
●
Reverse serial loopback – This is a loopback after
the receiver’s CDR block to the transmitter buffer.
The RX path in the PCS is active but the TX side
is not.
●
Reverse serial loopback (pre-CDR)
– This is the
loopback before the receiver’s CDR block to the
transmitter buffer. The RX path in the PCS is
active but the TX side is not.
●
PRBS/Serial loopback – This is another serial
loopback mode, but with the PRBS BIST block
active. The PRBS pattern depends on the
SERDES factor.
●
X4 – This mode can be used to implement SFI-5
interface. In this mode, all four channels within the
transceiver block are clocked from its central clock
divider block to minimize the transmitter
channel-to-channel skew.
Loopback Modes and
Built-In Self-Test Modes
sections in the
Stratix II GX Transceiver
Architecture Overview
chapter in volume 2 of the
Stratix II GX Device
Handbook.
Enforce default settings for
this protocol
This selection is not active in Basic mode because
there is no pre-defined protocol.
What is the operation mode? The available operation modes are receiver only,
transmitter only, and receiver and transmitter.
What is the number of
channels?
This option determines how many duplicate channels
this ALT2GXB instance contains.