🚀 go-pugleaf

In article <widow.723866984@camelot> widow@camelot.bradley.edu (Shaun Burnett) writes:
>
>	I know that the RS-232 voltage levels are +9 V for high level
>	and -9 V for a low level.  However, how far can you deviate
>	under +9 V and still have the signal considered a high level?
>	Also, how high can the voltage be increased from -9 V and
>	still have the signal considered a low level signal?
>
>	Thanks.
>

The RS-232C and V.28 specifications state a 0 logic level is greater than 
+3 volts and a 1 logic level is less than -3 volts.  Most modern chips 
surpass this standard and will switch between a 1 at .8 volts and a 0
at 2.4 volts.  Hysteresis is 200mV for the MAX2XX series and the delay
time is 350nS for negative going inputs and 650nS for positive going
inputs.
The specification provides for serial communications at up to 20,000 baud
at 50 feet provided capacitance is less than 2500pF.  (Cable length can 
be greater but distributed load capacitance must remain under 2500pF)

Regards,
Jeff