ASR-33 Data Format?

From: Philip.Belben_at_pgen.com <(Philip.Belben_at_pgen.com)>
Date: Wed Mar 31 10:50:53 1999

> Bzzzt!
>
> In asychronous communication, the rated speed of the channel in bits per
> second *includes* the start, stop, and parity bits.
>
> The ASR-33 did transmit (and receive) 110 bits per second, even though
> only 70 (not 80) were usable data.


I think the figure is 80, not 70, for the usable data. (I won't get into the
baud/bps argument). Ten whole characters. The ASR-33 doesn't do anything to
the msb, except have an option to generate parity there in the _keyboard_. You
can send ten 8-bit characters per second, 80 bits of data, to a TTY and all 80
bits will appear on the punch. You can read ten characters per second from the
punch and all 80 bits will be sent down the line. It's only typing on the
keyboard in which usefulness is restricted to 70 bits.

Philip.
Received on Wed Mar 31 1999 - 10:50:53 BST