Altera Stratix II GX Embedded Gigabit Ethernet MAC/PHY - Manual (Page 11)

Stratix II GX Embedded Gigabit Ethernet MAC / PHY
User's Guide
Version 1.0 - October 2005
Frame length increment Bytes
Frame payload length increment. During
simulation frames are generated starting from
"length of first frame" incrementing with each
frame generated.
1
Generated Frames max.
payload length
Bytes
Defines the payload maximum length used by the
Ethernet Generator models. This value specifies
the wrap around for the frame length of generated
frames. I.e. if the frame length increment would
exceed this value it wraps around to zero. Can be
used to test frame length error detection, when set
to any value larger than the MAC length
configuration.
1500
Enable Padding of Frames in
RX Path
Boolean
If enabled, RX PHY Generator model generated
frames are padded to 64 octets in length (normal
mode). If disabled, no padding occurs and
erroneous frames will be sent to the MAC RX.
True
Enable VLAN frames for all
tests
Boolean
If enabled, all frames sent/received will be VLAN
type of frames
False
Stop RX FIFO read after Frames
Inhibits the Testbench RX FIFO monitor reading
the RX FIFO, after this amount of frames has
been sent to the RX.
Can be used to test Flow-Control behaviour. If
more frames are received, the FIFO will get filled.
When the threshold level is reached, a Pause-
Frame will be generated by the MAC TX. If set to
0, the RX FIFO read is never paused.
0
Restart RX FIFO read after
RX FIFO
clocks
Number of clock cycles, the RX FIFO should not
be read after it has been stopped. Only relevant if
the previous configuration (read stop) was set to a
non-null value.
After this number of RX FIFO clock cycles, the RX
FIFO will be emptied again.
10
Generate Frames with Errors
on Transmit FIFO Interface
Boolean
Enable Transmit Error Generation the Core
Transmit Interface. When selected, the transmit
FIFO signal ff_tx_err is asserted with
ff_tx_eop
to signal an Error. When disabled,
the FIFO error is signalled, ff_tx_err is never
set to '1'.
False
Testbench reacts on Pause
Frames
Boolean
If enabled (true) the Testbench will stop the RX
(PHY) Frame generator, if the MAC sends a
Pause Frame. This simulates a usual flow-control
chain correctly.
If disabled (False) Pause Frames sent by the
MAC are ignored by the Testbench and the RX
(PHY) Frame generator will never pause. This can
be used to test the MACs FIFO overflow behavior.
This option has no effect, if loopback mode is
enabled (i.e. Frame generation in RX path is set
0).
True
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