[comp.sys.sun] "Can Sun 3 keyboard generate a break?"

gfr@wolfgang.mitre.org (Glenn Roberts) (01/04/89)

> 'Is there a way for the Sun 3 keyboard to generate a "break"?'

Recall that "break" is not an ASCII character, per say, but a SIGNAL that
is defined for RS 232 (and similar) communication lines.  The "break"
signal holds the line low (high?) for more than one character frame period
(some implementations have a fixed time, e.g. 250 ms.).

I'm sorry if my defnition is fuzzy, the point here is that "break" must be
produced by the UART chip handling your serial line, not by the keyboard.
Most terminal line handlers provide some way to produce the "break"
signal, for example in 'tip' the sequence "~#" generates a break.

- Glenn Roberts, The MITRE Corp., McLean VA (703)-883-6820
  gfr%wolfgang@gateway.mitre.org