Development Tools User’s Manual
73
IXP2400/IXP2800 Network Processors
Developer Workbench
Note:
If you select
SPI4
as the device type, the
Create Media Bus Device
dialog box will display the
defaults for the controls shown in
in the
Device parameters
section:
Number of ports,
Bus cycle threshold, Base port address, Minimum burst size, Maximum burst 1, Enable Tx
flow control, and Training frequency
.
If you select a device type other than
SPI4
(CSIX, SPHY, etc.), the
Device parameters
will be re-
positioned on the screen as appropriate to the device type.
Bus cycle threshold
This value determines the default maximum # of MSF cycles (one cycle
is equal to 2 bytes) per burst. A long burst will be broken into small
bursts with non-payload cycles inserted
Base port address
The base address of a SPI4 MAC device. The SPI4 supports 8-bit
address, so for a device with 10-port, the base port address could be
between 0 and 245. The SPI4 device assigns consecutive address to ports
of the same device. So, for a device of 10-port with base port address of
220. The port address space for this device will be 220 to 229.
Minimum burst size
This value determines the minimum number of bytes that the SPI4
device will transfer in one transaction, unless EOP is reached.
Figure 18. The Create Media Bus Device Dialog Box for CSIX