SMSC COM20020 Home Theater Server User Manual


 
7
Invitation
to Transmit to
this ID?
Y
N
Free Buffer
Enquiry to
this ID?
SOH?
Y N
Y N
RI?
Write SID
to Buffer
DID
=0?
DID
=ID?
Write Buffer
with Packet
CRC
OK?
LENGTH
OK?
DID
=0?
DID
=ID?
SEND ACK
N
Y
N
Y
N
Y
N
Broadcast
Enabled?
N
Y
N
No Activity
for 82
uS?
Y
N
Set NID=ID
Start Timer:
T=(255-ID)
Activity
On Line?
Y
N
T=0?
Set RI
RI?
Transmit
NAK
Transmit
ACK
Set NID=ID
Write ID to
RAM Buffer
Send
Reconfigure
Burst
Power On
Reconfigure
Timer has
Timed Out
Start
Reconfiguration
Timer (840 mS)
TA?
Broadcast?
Transmit
Free Buffer
Enquiry
No
Activity
Pass the
Token
Set TA
Y
N
ACK?
NAK?
1
No
Activity
NY
Increment
NID
Send
Packet
Was Packet
Broadcast?
No
Activity
N
ACK? Set TMA
Set TA
x 146 us
for 74.7
us?
for 74.7
us?
for 74.7
us?
YN
N
Y
Y N
NY
N
N
N
N
1
Y
Y
Y
Y
Y
Y
Y
N
Y
Read Node ID
ID refers to the identification number of the ID assigned to this node.
NID refers to the next identification number that receives the token after
after this ID passes it.
-
-
-
-
SID refers to the source identification.
DID refers to the destination identification.
SOH refers to the start of header character; preceeds all data packets.
-
Y N
FIGURE 1 - COM20020 OPERATION