Wirt Atmar wrote:

>I wrote that a BREAK was an abnormally long mark, while
>Bruce wrote that it was an abnormally long space. Because I wrote my answer
>from memory, I'm not sure that I'm right -- but I can say with absolute
>certainty that either Bruce or I is correct :-).

I just verified it (with my handy 1981 Z-80 data book): the line is held
at mark when idle, and a BREAK is an abnormally long period of "space".
The Z-80 SIO uses a definition of "null character plus framing error" to
detect BREAK; this corresponds to 10 bit times of space, which is the
minimum possible.

-- Bruce


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