COM20020I3V-HT SMSC, COM20020I3V-HT Datasheet - Page 29

• Manufacturer Part Number: COM20020I3V-HT
• Description: Network Controller & Processor ICs ARCNET Contrllr
• Manufacturer: SMSC

Specifications of COM20020I3V-HT

• Product: Controller Area Network (CAN)
• Number Of Transceivers: 1
• Data Rate: 5 Mbps
• Supply Voltage (max): 3.465 V
• Supply Voltage (min): 3.135 V
• Supply Current (max): 35 mA
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Package / Case: TQFP-48
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

SMSC COM20020I 3.3V Rev.E
5Mbps ARCNET (ANSI 878.1) Controller with 2K x 8 On-Chip RAM
BIT
7
6
5
4
3
2
1
0
My
Reconfiguration
Duplicate ID
Receive
Activity
Token Seen
Excessive NAK
Tentative ID
New Next ID
(Reserved)
BIT NAME
MY-
RECON
DUPID
RCVACT
TOKEN
EXCNAK
TENTID
NEW
NXTID
SYMBOL
Table 5 - DIAGNOSTIC STATUS REGISTER
This bit, if high, indicates that a past reconfiguration was caused by
this node. It is set when the Lost Token Timer times out, and
should be typically read following an interrupt caused by RECON.
Refer to the Improved Diagnostics section for further detail.
This bit, if high, indicates that the value in the Node ID Register
matches both Destination ID characters of the token and a
response to this token has occurred.
verified. A logic "1" on this bit indicates a duplicate Node ID, thus
the user should write a new value into the Node ID Register. This bit
is only useful for duplicate ID detection when the device is off line,
that is, when the transmitter is disabled. When the device is on
line this bit will be set every time the device gets the token. This bit
is reset automatically upon reading the Diagnostic Status Register.
Refer to the Improved Diagnostics section for further detail.
This bit, if high, indicates that data activity (logic "1") was detected
on the RXIN pin of the device. Refer to the Improved Diagnostics
section for further detail.
This bit, if high, indicates that a token has been seen on the
network, sent by a node other than this one.
Improved Diagnostic section for further detail.
This bit, if high, indicates that either 128 or 4 Negative
Acknowledgements have occurred in response to the Free Buffer
Enquiry.
command. Reading the Diagnostic Status Register does not clear
this bit.
corresponding bit in the IMR is also set. Refer to the Improved
Diagnostics section for further detail.
This bit, if high, indicates that a response to a token whose DID
matches the value in the Tentative ID Register has occurred. The
second DID and the trailing zero's are not checked. Since each
node sees every token passed around the network, this feature can
be used with the device on-line in order to build and update a
network map.
further detail.
This bit, if high, indicates that the Next ID Register has been
updated and that a node has either joined or left the network.
Reading the Diagnostic Status Register does not clear this bit. This
bit, when set, will cause an interrupt if the corresponding bit in the
IMR is also set. The bit is cleared by reading the Next ID Register.
This bit is undefined.
DATASHEET
This bit, when set, will cause an interrupt if the
This bit is cleared upon the "POR Clear Flags"
Page 29
Refer to the Improved Diagnostics section for
DESCRIPTION
Trailing zero's are also
Refer to the
Revision 09-11-06