5Mbps ARCNET (ANSI 878.1) Controller with 2K x 8 On-Chip RAM
Datasheet
A0
/n
MU
X
A1
A2
/B
AL
E
ADDRESS
DECODING
CIRCUITRY
2K x 8
RAM
ADDITIONAL
REGISTERS
AD0-AD2,
D3-D7
STATUS/
COMMAND
REGISTER
nPULSE1
nPULSE2
nTXEN
nINTR
TX/RX
LOGIC
MICRO-
SEQUENCER
AND
RXIN
WORKING
REGISTERS
RESET
LOGIC
nRESET
XTAL1
XTAL2
OSCILLATOR
nRD/nDS
nWR/DIR
nCS
BUS
ARBITRATION
CIRCUITRY
NODE ID
LOGIC
RECONFIGURATION
TIMER
Figure 5.6 - Internal Block Diagram
Table 5.1 - Typical Media
NOMINAL
ATTENUATION PER 1000 FT.
CABLE TYPE
IMPEDANCE
AT 5 MHZ
RG-62 Belden #86262
5.5dB
93Ω
75Ω
RG-59/U Belden #89108
RG-11/U Belden #89108
IBM Type 1* Belden #89688
7.0dB
5.5dB
7.0dB
75Ω
150Ω
IBM Type 3* Telephone Twisted Pair
Belden #1155A
17.9dB
16.0dB
100Ω
COMCODE 26 AWG Twisted Pair
Part #105-064-703
105Ω
*Non-plenum-rated cables of this type are also available.
Revision 12-05-06
Page 24
SMSC COM20020I Rev D
DATASHEET
SMSC [ SMSC CORPORATION ]
