15 Nov
2019
15 Nov
'19
5:43 a.m.
On Thu, Nov 14, 2019, 10:30 PM Jim Brain via cctalk <cctalk at classiccmp.org wrote:
On 11/14/2019 11:05 PM, Brent Hilpert via cctalk
wrote:
1200 baud hayes modems required the initial AT be all upper case. I can't
recall if the 2400 baud modem relaxed this, or if it was later version.
Also, AT introduced commands. +++ could be followed immediately by ATH to
hang up...
But the parity trick discussed here matches my memory as well...
Warner
(Without having gone through the code presented in full detail, but
thinking from
root premises.)
ASCII A = 0x41 --> 2 bits on
ASCII T = 0x54 --> 3 bits on
I agree, though I believe aT,At,AT,and at are all allowed, which
complicates things a bit aT is the bad one, where the calc for 7E1 and
7S1/8N1 yield the same values...