what is the difference between RS 232,RS 485,RS 422, how
they different from each other




Answer Posted / calvin

RS232 -
-- point to point
-- Distance 20m
-- Both Half duplex & full duplex
[half duplex --> Data can only be sent or received at
a time and not both same time]
[Full duplex --> data can be sent or received at the same
time]
-- An unbalanced signal --> represented by a single signal
wire where a voltage level on that one wire is used to
transmit/receive binary 1 and 0
-- min input level +/-3V
-- Very sensitive to noise

RS485
-- Multipoint
-- distance upto 1200m @ 100Kbps
-- only half duplex
-- min input level 200mV
-- less sensitive to noise

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