- Sun Installation and User's Guide GigaSwift Ethernet Adapter

42 Sun GigaSwift Ethernet Adapter Installation and User’s Guide • August 2004

If enable_ipg0 is disabled, the value of ipg0 is ignored and no additional delay is

set. Only the delays set by ipg1 and ipg2 will be used. Disable enable_ipg0 if

other systems keep sending a large number of back-to-back packets. Systems that

have enable_ipg0 set might not have enough time on the network.

You can add the additional delay by setting the ipg0 parameter from 0 to 255, which

is the media byte time delay.

TABLE 4-5 defines the enable_ipg0 and ipg0 parameters.

The ce device supports the programmable Interpacket Gap (IPG) parameters ipg1

and ipg2. The total IPG is the sum of ipg1 and ipg2. The total IPG is 0.096

microseconds for the link speed of 1000 Mbps.

TABLE 4-6 lists the default values and allowable values for the IPG parameters.

By default, the driver sets ipg1 to 8-byte time and ipg2 to 4-byte time, which are

the standard values. (Byte time is the time it takes to transmit one byte on the link,

with a link speed of 1000 Mbps.)

If your network has systems that use longer IPG (the sum of ipg1 and ipg2), and if

those systems seem to be slow in accessing the network, increase the values of ipg1

and ipg2 to match the longer IPGs of other machines.

TABLE 4-5 Parameters Defining enable_ipg0 and ipg0

Parameter Values Description

enable_ipg0 0

enable_ipg0 reset

enable_ipg0 set (Default=8)

ipg0 0 to 255 The additional time delay (or gap) before

transmitting a packet (after receiving the

packet) (Default=8)

TABLE 4-6 Read-Write Interpacket Gap Parameter Values and Descriptions

Parameter Values

(Byte-time)

Description

ipg1 0 to 255 Interpacket gap 1 (Default = 8)

ipg2 0 to 255 Interpacket gap 2 (Default = 4)