Hmm, but under RS232 the physical levels are +25..+3 Volt and -25..+2
Volt, that's why RS423 is RS232 "compatible", i.e. RS423 has:
I'm not going to bother looking up the actual rs-232 spec, but I'll do the
next best thing. John E. McNamara, "Technical Aspects of Data
Communication," page 49, table 5-2a, "Condensed EIA RS-232-C Electrical
Specifications," lists +15 -> +5 as space, -5 -> -15 as mark, and +5 -> -5
as "noise margin" and "transition region."
Furthermore, the input impedance for rs-232 is in the range of 3 to 7 K
ohms. At that impedance, any unterminated line is going to have at least a
volt or two of noise on it.
In addition, my experience has been that unterminated rs-232 lines give
unpredictable results.
I think you may have confused 232 with 423. I think the console port on the
rs6k is 232, not 423.
