KSZ8995XA Micrel Inc, KSZ8995XA Datasheet - Page 31

• Manufacturer Part Number: KSZ8995XA
• Description: IC SWITCH 10/100 5PORT 128PQFP
• Manufacturer: Micrel Inc

Specifications of KSZ8995XA

• Applications: *
• Mounting Type: Surface Mount
• Package / Case: 128-MQFP, 128-PQFP
• Number Of Primary Switch Ports: 5
• Internal Memory Buffer Size: 64
• Operating Supply Voltage (typ): 1.8/2.5/3.3V
• Fiber Support: Yes
• Integrated Led Drivers: Yes
• Phy/transceiver Interface: MII/SNI
• Power Supply Type: Analog/Digital
• Package Type: PQFP
• Data Rate (typ): 10/100Mbps
• Vlan Support: Yes
• Operating Temperature (max): 70C
• Operating Temperature (min): 0C
• Pin Count: 128
• Mounting: Surface Mount
• Jtag Support: No
• Operating Temperature Classification: Commercial
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: 576-1642 - BOARD EVALUATION FOR KSZ8995XA
• Lead Free Status / RoHS Status: Compliant, Lead free / RoHS Compliant
• Other names: 576-1042

May 2005
KS8995XA
Address
Register 4 (0x04): Global Control 2
7
6
5
4
3
2
1
0
Register 5 (0x05): Global Control 3
7
6
5
4
3-2
Name
Reserved
Multicast storm
protection disable
Reserved
Flow control and back
pressure fair mode
No excessive collision
drop
Huge packet support
Legal maximum packet
size check disable
Priority buffer reserve
Reserved
Reserved
Reserved
Reserved
Priority scheme select
Reserved
Reserved
Reserved
Reserved
Reserved
00 = always deliver high priority packets first.
01 = deliver high/low packets at ratio 10/1.
10 = deliver high/low packets at ratio 5/1.
11 = deliver high/low packets at ratio 2/1.
Description
1 = “Broadcast Storm Protection” does not include
multicast packets. Only DA=FFFFFFFFFFFF packets
will be regulated.
0 = “Broadcast Storm Protection” includes DA =
FFFFFFFFFFFF and DA[40] = 1 packets.
Reserved
1 = fair mode is selected. In this mode, if a flow control
port and a non-flow control port talk to the same
destination port, packets from the non-flow control port
may be dropped. This is to prevent the flow control port
from being flow controlled for an extended period of time.
0 = in this mode, if a flow control port and a non-flow
control port talk to the same destination port, the flow
control port will be flow controlled. This may not be “fair”
to the flow control port.
1 = the switch will not drop packets when 16 or more
collisions occur.
0 = the switch will drop packets when 16 or more
collisions occur.
1 = will accept packet sizes up to 1916 bytes (inclusive).
This bit setting will override setting from bit 1 of the
same register.
0 = the max packet size will be determined by bit 1 of
this register.
1 = will accept packet sizes up to 1536 bytes (inclusive).
0 = 1522 bytes for tagged packets (not including.
packets with STPID from CPU to ports 1-4), 1518 bytes
for untagged packets. Any packets larger than the
specified value will be dropped.
1 = each output queue is pre-allocated 48 buffers,
used exclusively for high priority packets. It is
recommended to enable this when priority queue
feature is turned on.
0 = no reserved buffers for high priority packets.
31
Mode
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Default
1
1
1
1
Pin PMRXD1 strap
option. Pull-down (0):
Drop excessive
collision packets.
Pull-up (1): Don’t
drop excessive
collision packets.
Note: PMRXD1
has internal pull-
down.
0
Pin PMRXER strap
option. Pull-down (0):
1518/1522 byte
packets. Pull-up
value will be
dropped. (1): 1536
byte packets
Note: PMRXER
has internal pull
down.
0
0
0
0
0
00
M9999-051305
Micrel, Inc.