MUSIC MU9C8328-RDC Datasheet

Preliminary Data Sheet

MU9C8328 Ethernet Interface

APPLICA TION BENEFITS

Ø Single port 10 MHz Ethernet address parsing,

filtering, and learning state machine at wire
speed

Ø Glue-free interface between the MUSIC

LANCAM® Family and AMD, National,
Motorola, or similar Ethernet Controllers
having an NRZ serial data port

Ø Selectable filtering and learning decisions

on DA and SA compares

Ø Supports cascaded MUSIC LANCAM series

for long station lists

Ø Host processor port for LANCAM

initialization and housekeeping activities

Ø Supports system clock rates from 20 MHz to

33 MHz

Ø 100-pin PQFP package
Ø 5 Volt operation

GENERAL DESCRIPTION

The MU9C8328 speeds up bridging operations using
Ethernet controller chips with serial NRZ data outputs,
such as AMD’s MACE™, National’s SONIC™, and
Motorola’s QUICC™ controllers, by parsing the Ethernet
frame independently of the Ethernet controller device, and
notifying it whether to accept or reject the incoming frame.
The MU9C8328 supports both positive and negative
filtering on the Destination address and learning of new
Source addresses, by efficiently controlling the compare
activities of the MUSIC LANCAM Family. Filtering and
learning routines are user configurable. These routines
are automatically invoked by the internal state machine
based on the contents of the incoming frame and the
configuration settings. For aging and other housekeeping
routines, the MU9C8328 provides the proper sequencing
and timing of LANCAM accesses for an external
processor.

The MU9C8328 receives serial NRZ data from the
Ethernet controller chip, finds the Start delimiter, and
loads the DA and SA into registers. The DA is sent to the
LANCAM for filtering and, depending on the filter action

/E

/CM

/W

/EC

/M F

DQ(15-0)

PROCESSOR

INTERFACE

SERCLK

SERDAT

/N E TRD Y

/REJ ECT

NETW OR K

INTERFACE

/FF

LANC AM IN TER FACE

STATE

MACHINE

CO NT RO L

STAT US

OP-C ODE

ASS OCIATED D ATA

Block Diagram

MUSIC Semiconductors, the MUSIC logo, the phrase “MUSIC Semiconductors”, and LANCAM are registered trademarks of MUSIC
Semiconductors. All other trademarks are registered by their respective owners. MUSIC is a trademark of MUSIC Semiconductors.

/CS
/AS
/W E

3

A(2-0)

D(15-0)

READY
/INT
SYSCLK
/RESET

11 February 1999 Rev. 4a

MU9C8328 Ethernet Interface

GENERAL DESCRIPTION

selected, notifies the controller whether to copy or purge
the frame. The SA is then sent to the LANCAM for
comparison, and if no match is found, can be learned
to the Next Free address in the LANCAM. Scheduling
is done within the MU9C8328 so that each filtering
action completes in the time of a minimum length
frame. The filtering and learning routines are
preprogrammed in the MU9C8328, with decision
options set in the control register. A Status register is
provided so the host processor can determine the results
of activities. The specific Op-Code for the LANCAM

Continued

learning instruction is by default a MOV NF , CR, V, but it
can be overridden by writing a value to the Op-Code
register. Aging and purging activity is directly controlled
by the host processor. The READY signal notifies the host
processor that processor operations are complete. The /
INT signal notifies the processor that a network frame
has been processed and the result stored in the Status
register. The processor can turn off the network filtering
activity to have total control of the LANCAM; during this
time the controller can be notified to accept or reject

all frames.

PIN DESCRIPTIONS

All signals are implemented in CMOS technology with TTL levels. Signal names that start with a slash (“/”) are active
LOW. Inputs should never be left floating. Refer to the Electrical Characteristics section for more information.

NETWORK INTERFACE

SERCLK (Serial Clock, Input, TTL)

SERCLK is the nominally 10 MHz clock from the Ethernet
controller chip to the MU9C8328. Frame parsing begins
only after the internal clock detector determines that
SERCLK is valid. Internally pulled down with nominal
50K resistor.

SERDAT (Serial Data, Input, TTL)

SERDAT is the NRZ data from the 10 MHz Ethernet
controller chip. The MU9C8328 uses SERCLK to strobe
SERDAT looking for a Start Frame delimiter (SFD), at
which point it begins filtering and learning activity on
the Destination Address (DA) and Source Address (SA).

/REJECT (Reject, Output, TTL)

The MU9C8328 takes /REJECT LOW to notify the
Ethernet controller chip to reject a frame under conditions
set in the Filter Control register.

/NETRDY (Network Ready, Input, TTL)

If /NETRDY is LOW, the MU9C8328 begins parsing
frame data received on the SERDAT input if SERCLK is
valid. The Ethernet controller chip, or the user, takes
/NETRDY HIGH to indicate that SERCLK or SERDAT
is invalid or is transmitting. The MU9C8328 frame parser
and internal state machines are returned to an idle state
after safely completing any LANCAM activity, while
ignoring any compare results. Internally pulled down with
nominal 50K resistor.

PROCESSOR INTERFACE

SYSCLK (System Clock, Input, TTL)

SYSCLK is a 20 MHz to 33 MHz continuous
clock provided by the host system and is the master clock
within the MU9C8328. It is used to determine the presence
of a valid clock on the SERCLK input, operate the three
internal state machines, and provide the proper timing of
the signals on the LANCAM port. If SYSCLK is below
30 MHz, a LANCAM speed grade of 120 ns is acceptable.
Above 30 MHz, a LANCAM speed grade of 90 ns or better
is required.

/CS (Chip Select, Input, TTL)

/CS is taken LOW by the host processor to gain access to
the registers of the MU9C8328 or to directly access the
LANCAM through the MU9C8328 internal
LANCAM registers. The state of /CS becomes effective
on the rising edge of SYSCLK. When /CS goes HIGH,
the MU9C8328 continues filtering and learning based on
conditions set in the Filter Control register and the frame
activity on the network interface.

/AS (Address Strobe, Input, TTL)

The falling edge of /AS latches the A(2–0) bus, and when
both /AS and /CS are LOW, the processor state machine
is enabled by first rising edge of the SYSCLK to begin
writes into or reads out of the MU9C8328.

Rev . 4a 2

MU9C8328 Ethernet Interface

/

PIN DESCRIPTIONS

/WE (Write Enable, Input, TTL)

/WE determines the direction of data flow into or out of
the MU9C8328’s processor interface. It also determines
the state of /W to the LANCAM when the processor is
accessing the MU9C8328’s internal LANCAM registers.
If /WE is LOW , the data is written into the register selected
by the A(2–0) bus. If /WE is HIGH, then data is read
out of the register selected by the A(2–0) bus.

A(2–0) (Address Bus, Input, TTL)

A(2–0) select the internal register in the MU9C8328
accessed by the host processor as shown in Table 1.
A(2–0) are latched by the falling edge of /AS.

D(15–0) (Data Bus, I/O, Three-state TTL)

D(15–0) is the processor data bus into and out of the
MU9C8328, and is demuxed to the internal registers as
selected by the A(2–0) bus. If the register selected is the
Control, Status or Op-Code register, when /WE is LOW,
D(15–0) is loaded on the second rising edge of SYSCLK
after both /AS and /CS are LOW. When /WE is HIGH,
data from the selected register is output to the D(15–0)

Continued

bus on the second rising edge of SYSLCK after both /AS
and /CS are LOW. For CAM access, the write or read
operation is completed when READY returns HIGH. If
/CS is HIGH, or if data is not being read out of the
MU9C8328, the output buffers go to HIGH-Z. Internally
pulled down with nominal 50K resistor.

READY (Ready, Output, Three-state, TTL)

When writing to the Control, Status, or Op-Code register,
READY goes LOW on the first rising edge of SYSCLK
after both /AS and /CS are LOW and returns HIGH on the
next rising edge of SYSCLK. For a read cycle from those
registers, READY may only show a negative-going spike
at the first rising edge of SYSCLK after both /AS and /CS
are LOW. The data will be valid before the next rising
edge of SYSCLK. When writing or reading to/from the
CAM registers, READY will go LOW on the first rising
edge of SYSCLK after both /CS and /AS are LOW.
READY returns HIGH four SYSCLK cycles later,
indicating that the CAM write cycle will complete after
the next rising edge of SYSCLK.

/FF

/M F

/E C

/CM

GND

VCC

RESET
READY

/INT

/W E

/AS

/CS

DQ15

DQ13

DQ12

8

A2

DQ11

73

72

71

9

10

D15

D14

GND

VCC

80

79

77

78

81
82
83
84
85
86

/E

/W

87
88
89
90
91
92
93

94
95

96
97

98
99

100

2

4

3

1

VCC

GND

SYSCLK

A1

DQ14

75

76

74

7

5

6

A0

GND

DQ10

70

69

68

67

DQ7

DQ9

DQ8

VCC

65

66

64

63

MU9C8328-RDC

100-pin PQFP

(Top View)

17

14

11

12

13

15

16

18

D9

D13

D12

D11

GND

D8

D10

VCC

PINOUT DIAGRAM

DQ6

19

D7

DQ5

DQ4

60

62

61

20

21

D6

D5

59

22

D4

DQ1

DQ2

DQ0

VCC

DQ3

58

57

56

23

24

25

D3

D2

GND

55

54

53

52

51

50
49
48
47
46
45
44
43
42
41
40
39
38
37

36
35

34
33
32

31

27

26

28

29

30

D1

VCC

GND

SERCLK
SE RDAT

/REJECT

NTE ST OUT

NTEST_ E N

GND
VCC

/NE TRDY

D0

3

Rev . 4a

MU9C8328 Ethernet Interface

PIN DESCRIPTIONS

/INT (Interrupt, Output, Three-state TTL)
/INT goes LOW to signal the processor that a frame has
been processed, and the results loaded into the Status
register. /INT returns HIGH when the Status register is read.

/RESET (Reset, Input, TTL)

When /RESET is taken LOW, all the internal state
machines are reset to their initial state. Any data stored in
the input address parser is cleared, and the Control, Status,
and Learn Op-Code registers are reset to their default
values. /RESET is synchronous and should be held LOW
for a minimum of two SYSCLK cycles. The user must set
the LANCAM Segment Control register after asserting
/RESET.

LANCAM INTERF ACE

DQ(15–0) (CAM Data Bus, I/O, Three-state TTL)

The DQ(15–0) bus communicates 16-bit data or
instructions between the MU9C8328 and the
LANCAM. When no data is being transmitted by either,
the bus goes HIGH-Z. Internally pulled down with nominal
50K resistor.

Continued

MU9C8328 is outputting data for the LANCAM to place
in its data registers or memory. If /CM is HIGH while /W
is HIGH, the LANCAM is outputting data from one of its
data registers or memory to the MU9C8328.

/EC (Enable Daisy Chain, Output, TTL)

The MU9C8328 takes /EC LOW to control a daisy chain
of LANCAMs by generating the /MF output from the
LANCAM in the case of a match between the contents of
its Comparand register and its memory . When /EC is LOW ,
only the LANCAM containing the match will respond to
write cycles, or output read data. When /EC is HIGH, all
LANCAMs will respond to write cycles.

/MF (Match Flag, Input, TTL)

The LANCAM takes /MF LOW to indicate to the
MU9C8328 that a match was found in its memory with
the contents of its Comparand register. /MF returns HIGH
after the MU9C8328 takes /EC HIGH, or the match
condition is no longer valid. In a daisy chain of
LANCAMs, the /MF signal comes from the /MF output
of the last LANCAM in the string. Internally pulled down
with nominal 50K resistor.

/E (Chip Enable, Output, TTL)

The MU9C8328 takes /E LOW to initiate LANCAM
activity by registering the /W, /CM, /EC, and DQ(15–0)
signals into the LANCAM. /E is taken HIGH to register
returning data into the MU9C8328.

/W (Write Gate, Output, TTL)

The MU9C8328 outputs /W to control the direction of
data flow between the MU9C8328 and the LANCAM. If
/W is LOW at the falling edge of /E, the MU9C8328 is
outputting data to the DQ(15–0) bus for the LANCAM to
input. When /W is HIGH at the falling edge of /E, the
LANCAM outputs data to the DQ(15–0) bus for input to
the MU9C8328.

/CM (Data/Command Select, Output, TTL)

The MU9C8328 outputs /CM to control whether
the LANCAM interprets the DQ(15–0) bus as containing
command information or data. If both /CM and /W are
LOW at the falling edge of /E, the MU9C8328 is outputting
an instruction for the LANCAM to execute, or a value for
one of the LANCAM configuration registers. If /CM is
LOW while /W is HIGH, then the LANCAM will be
outputting data from one of its configuration registers to
the MU9C8328. If /CM is HIGH while /W is LOW, the

/FF (Full Flag, Input, TTL)

The LANCAM takes /FF LOW to indicate to the
MU9C8328 that the LANCAM has no empty locations
remaining. /FF is taken HIGH when the LANCAM has
one or more locations still empty. In a daisy chain of
LANCAMs, the /FF signal comes from the /FF output pin
of the last LANCAM in the string. Internally pulled down
with nominal 50K resistor.

POWER AND GROUND

VCC, GND (Positive Power Supply, Ground)

The VCC pins must be connected externally to a power
source regulated to 5.0 ± 0.25 volts, and should be
adequately bypassed to the Ground pins through
both high and low frequency capacitors. The Ground pins
should all be connected to a common ground plane.

NTTESTOUT

Reserved - Do not connect.

NTEST_EN

Reserved - Tie low.

Rev . 4a 4

MU9C8328 Ethernet Interface

FUNCTIONAL DESCRIPTION

The MU9C8328 works with the MUSIC LANCAMs to
provide a complementary and versatile 10 MHz Ethernet
filtering solution for bridges, routers, and switches. Using
the serial NRZ data stream and clock available from many
Ethernet controller chips, the MU9C8328 parses the
incoming frame, finds the Start Delimiter, and forms the
Destination and Source addresses into 16-bit words for
relay to the LANCAM. After all three 16-bit DA segments
have been loaded into the LANCAM, an automatic
compare occurs between the incoming DA and the 48-bit
MAC addresses stored in the LANCAM. If a match is
found, the MU9C8328 is notified, and if Control Register
bit 5 is set for negative filtering, the /REJECT line will be
asserted if Control Register bit 3 is set. An interrupt can
also be generated over the /INT pin if Control Register bit
8 is set. Also, if Control Register bit 0 is set, the Associated
data in segment 0 of the matching entry in the LANCAM
will be retrieved and stored in the Associated Data register
for reading by the host processor. If a match is not found
on the DA, and Control Register bit 5 was set for positive
filtering, the /REJECT line will be asserted. An interrupt
can also be enabled for a no-match on a DA using Control
Register bit 10.

After the DA filtering, the Source Address is loaded
into the LANCAM in three segments. Upon the last
SA load, an automatic compare again takes place. If
there is a match between the SA and an entry in the
CAM, and Control Register bit 7 was set, an interrupt
is asserted. Positive and negative filtering on the SA is
also possible, set by Control Register bit 4, and the /INT
pin may be asserted as well. In the case of a no-match
on an SA, the SA can be automatically “learned” (i.e.,
moved to the first empty location in the LANCAM) if
Control Register bit 1 is set.

If a Loss of Carrier is detected by SERCLK staying LOW
for more than 16 SYSCLK cycles, an interrupt is triggered
if Control Register bit 12 is set. This interrupt also activates
if a collision is detected.

The host processor can access the MU9C8328, shown in
T able 1, at any time, even when a frame is being processed.
Access to the LANCAM through the LANCAM access
registers (04H to 07H) is arbitrated, however, with the
network having precedence. The host processor can have
control of the LANCAM by setting the Network Enable
bit in the Control register (bit 13) to a 0, which will disable
network filtering until it is returned to a 1. While disabled,
bit 14 in the Control register sets the MU9C8328 to accept
all frames by keeping /REJECT HIGH, or to reject all
frames by keeping /REJECT LOW.

Registers 04H through 07H allow the host processor access
to the LANCAM for Command and Data Write and Read
cycles, with /EC HIGH or LOW. This is often needed for
housekeeping activities, such as preventing the LANCAM
from becoming full by aging out old entries based on
timestamps stored in the Associated data (Segment 0) of
the LANCAM memory.

The /INT pin will go LOW at the end of the SA field to
indicate an interrupt for any of the reasons set in the
Control register. Reading the Status register to discover
the nature of the interrupt will take the /INT pin HIGH
again. The READY signal goes LOW after a host processor
write to a register or the LANCAM to indicate that the
Write cycle has begun and return HIGH after a fixed
number of SYSCLK cycles. It will also go LOW during a
read from the LANCAM and return HIGH when the data
from the LANCAM is valid. Since a network compare
activity has precedence over a host process access to the
LANCAM, READY will stay LOW until the network
activity is complete and the host-induced LANCAM read
has completed.

Figure 1 shows a typical network filtering sequence, where
the MU9C8328’s Control register was set to 2109H. This
setting enables network filtering, enables an interrupt for
a match found on the DA, enables negative filtering on
the DA (reject if a DA match is found), enables asserting
the /REJECT pin for compares on the DA, and enables
retrieving the Associated Data field from the matching
location in the LANCAM.

5

Rev . 4a