Framing errors and autobaud @ 2400

[code 101]

CR is not the best character for generating a framing error.  you want
the receiver to see a 0 where it expects to see the stop bit.  since CR
is 00001101, the receiver sees the reversal of this bit string (rs232
is little-endian), with start and stop bits added, and every bit
repeated, i.e., 001100111110000000011.

note the long string of 1's where you would like to have a 0.  the
second byte will also fail to generate a framing error since it ends
with the real stop bits.

your best bet for generating a framing error is to use the ascii
character that ends with the longest string of 0's: @, or 01000000.

this is why you frequently see "" @ and in:- at -in: in uucp login
scripts.  @ also has the happy side effect of clearing out line noise,
except in 4.2bsd where the convention was unilaterally changed.

	peter