File: EP4.bravo
By: L. Stewart
Date: June 10, 1981 11:19 AM

This contains some justification for adding audio to the auxiliary board.

The main line of the audio project should remain the stand-alone Etherphone. This device can be used both for telephony and for integrated functions (voice mail, annotation). Obviously, one’s workstation can treat the office Etherphone as a peripheral. The Etherphone has all the functionality of workstation based audio, but the reverse is not true.

Nevertheless, there is a place for workstation based audio:

1. It is not very expensive, when added to a board built for other reasons. (There may be additional leverage if D-machine IO to scanners and such can be done by a T1 line.) Because it doesn’t cost much (especially if parts are not actually plugged in), and the design time is small (for TTL anyway), we risk little even if we can’t find a use for it (but see below).

2. The date on which we can provide Etherphone for the masses is uncertain. We are talkng about 18-24 months for the Ether KTS. Sometime around then the components should be available for a 20-40 chip Etherphone, but we don’t know for sure. The workstation audio can get more audio to the rest of the lab sooner, even though it would be displaced by the arrival of Etherphones.

3. Our workstations have the cycles for audio if they are running an appropriate program. Since we cannot expect that to be true at all times, workstation audio cannot be used as the office telephone, but it can be used for the "integrated functions" like voice messages, annotation, editing, and so on.

Sometimes, telephony would work:

When a call is placed to a non-Etherphone location where there is workstation audio available, the originating Etherphone can check is it is running before resorting to the telephone company system.

When the owner of workstation audio places a call, the workstation could sieze an idle Etherphone and use it as a gateway. (This would prevent the owner of that Etherphone from getting outside calls, though ether calls would still work if the Etherphone has the cycles to handle two at once!)

4. Writing programs to use workstation audio might take resources away from the Etherphone, but providing a minimal interface might prompt others to do things with audio.