Bulletins from the Pacific Packet Radio Society - page 179

1.1 PACMMS operating system
1.1.1 Control computer interface - Telemetry to and from, commands from

1.1.2 Mass store system High level functions, OP EN/CLOSE/ READ/ WRITE Low level functions, get/put byte through serial interface.

1.1.3 Ground station interface Data acquisition - modem control, RF control low level protocol handlers collision control - channel scheduling High level protocol handlers Path management. Network node functions not requiring message system control - store and forward?

1.2 Application software
1.2.1 User management - logon, status. Maintain list of current active "users" (ground station in active communication).
1.2.2 File system
1.2.3 Mail system
1.2.4 Administrative functions - mass store purge, reconfiguration of memory or data links - possibly via control link.

2 Ground station
2.1 User interface software - user to PACMSS (1)
2.2 Data link control - protocol drivers
2.3 Ground station hardware control - RF, modem, low level IO.
2.4 Interface to ground based networks - network node - gateway to PACSAT

FILE QST.83.02.2l.0.WA7GXD

To: Paul Rinaldo
CC: Hank Magnuski
Re: 16-Transition Preframe Sync


I read your message dated 21 Feb regarding the sync requirements for the various HDLC controllers being used, or planned for use, in Packet radio (18273, WD1933, Z8530).

The WD specs are not as detailed as the Intel with regard to the number of transitions required to assure "look" to the center of the bit field. However, while Intel does provide a nonstandard sync command to assure sync, it is unclear to some of us at present just how important it is to be sampling the data at the "exact" center or the bit.

We are currently sending frame sync headers during transmitter keyup time and have noticed no problems directly attributable to

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