Bulletins from the Pacific Packet Radio Society - page 071

violating nodes. Note also that all information for giving out ID's is available at all nodes, so that the loss of the net control is handled trivially by the first station detecting loss picking up the NCS.


The current network layer must handle the functions normally associated with control of the local area channel, transport of messages and interfacing applications programs for these early networking experiments. Specific functions handled by this layer are :

support of datagrams and virtual circuits
opening and closing connections
data transfer
error control
message flow
routing of messages to destinations

The mechanism for flow control is the simple stop-and-go type of algorithm, identical to other packet implementations. Certain of the functions called out are also found in the link-level protocol, since these hooks are required to pass the functions through the channel. There will be more on this protocol written in the TAPR activities column by the Software Group, as "things develop".

FILE QST. 82.05.1 8.0.W4RI

TO : All
SUBJ: Am7910 Single-Chip Modem

You will be interested in reading the May 12 issue of EDN Magazine. More specifically, I refer to the article, starting on page 143, entitled "Single-chip FSK modem expands your design choices," by Michael K. Stauffer of Advanced Micro Devices Inc.

In one 28-pin chip, the Am7910 is able to become a Bell 103 originate, Bell 103 answer, Bell 202, V.21 originate, V.22 answer, or several flavors of V.23 by setting mode-control input lines.

I called Mike Stauffer for some more info. He said that samples would be available mid-June with production in August-September. The onesy price will be in the $35-40 range initially with quantity prices dropping to the $10-15 ballpark as they move down the "learning curve." The guy at AMD to talk to about samples, prices, and other marketing info is Ray Lett, 408-7322400 ext. 3774.

This chip looks good not only for Bell 202 packeting but phone-line applications. I intend to follow up on this and possibly build up something using this chip. I would appreciate any developments on this chip for the AMRAD Newsletter.

73, Paul, W4RI

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