MU9C8338 10/100Mb Ethernet Filter Interface
Software Model
SOFTWARE MODEL
System Registers
One set of registers is available to address the MU9C8338
component and its attached LANCAMs as a single system.
The application decodes one range of addresses to produce
a Processor Chip Select System signal (/PCSS). The
lowest address in this application-defined address range,
shown in Table 3, is referred to as SYSTEM_BASE.
Table 3: System Registers
Name
R/W
R
Description
Address
Default Settings
N/A
SSTAT
System Status
SYSTEM_BASE + 0H
SYSTEM_BASE + 1H
SYSTEM_BASE + 2H
SYSTEM_BASE + 3H
SYSTEM_BASE + 5H
SYSTEM_BASE + 6H
SYSTEM_BASE + 7H
SYSTEM_BASE + 8H
SYSTEM_BASE + 9H
SYSTEM_BASE + AH
SYSTEM_BASE + CH
SYSTEM_BASE + DH
SYSTEM_BASE + EH
SYSTEM_BASE + 10H
SYSTEM_BASE + 11H
SYSTEM_BASE + 12H
SYSTEM_BASE + 20H
SYSTEM_BASE + 21H
SYSTEM_BASE + 24H
SYSTEM_BASE + 26H
SYSTEM_BASE + 27H
SYSTEM_BASE + 28H
SYSTEM_BASE + 29H
SSCFG
W
System Static Configuration
System Dynamic Configuration
System Targets
0000H
0H
SDCFG
W
STARG
W
0H
SCDW0
R/W
R/W
R/W
R/W
R
CAM Data Word 0
N/A
SCDW1
CAM Data Word 1
N/A
SCDW2
CAM Data Word 2
N/A
SCDW3
CAM Data Word 3
N/A
STPURG
STCURR
SMXSADACYC
SCSWB
Time Stamp to Purge
01H
R
Time Stamp Current
00H
W
Max SA/DA Cycle
20H
R
CAM Status Word B
N/A
SCSWA
R
CAM Status Word A
N/A
SSAU
W
SA Update Op-Code
0368H
0334H
0FH
SSAL
W
SA Learn Op-Code
SLCCS
W
LANCAM Control Signals
Perform Delete Sequence
Perform Add Sequence
Perform Read Sequence
Perform Increment STCURR Sequence
Perform Increment STPURG Sequence
Perform Increment STCURR & STPURG Sequence
Perform SetAddr. Sequence
SDO_DELETE
SDO_ADD
SDO_READ
SDO_INCTS
SDO_INCPR
SDO_INCTSPR
SDO_SETADD
W
N/A
W
N/A
W
N/A
W
N/A
W
N/A
W
N/A
W
N/A
System Status Register
Table 5 shows a CAM_SPD setting for a 120 ns speed
grade LANCAM component. 120 ns LANCAMs are no
longer available and it is recommended that when using a
90 ns LANCAM, set SSCFG[3:1] to 000. This setting
accommodates most applications and has the added
benefit of using the least amount of power.
The System Status register (SSTAT) provides a CPU
visibility into the state of the LANCAM array. The /FF bit
indicates the current state of the Full Flag output of the
LANCAM array. The /MF bit indicates the Match Flag
output of the LANCAM array.
Table 5: SSCFG: System Static Configuration
Register
Table 4: SSTAT: System Status Register Mapping
Name
/FF
Bits
0
Description
Name
Bits
Description
Full Flag from LANCAM array
Match Flag from LANCAM array
CAM_SPD
3:1
000 = 120 ns (90 ns)
001 = 90 ns
/MF
1
010 = 70 ns
System Static Configuration Register
011 = RESERVED
100 = RESERVED
101 = RESERVED
110 = RESERVED
111 = RESERVED
The System Static Configuration register (SSCFG) allows
the CPU to configure the LANCAM array. These are set
and forget values. The CAM_SPD sets the controller to
match the speed grade of the LANCAM components
attached. A 50MHz clock is assumed. The INV_REJ bit
configures the REJ port to be active LOW instead of active
HIGH.
INV_REJ
0
0 = Active HIGH
1 = Active LOW
12
Rev. 1a